diff --git a/01-rstudio-intro.html b/01-rstudio-intro.html
index 4c759526d..5c3c8b698 100644
--- a/01-rstudio-intro.html
+++ b/01-rstudio-intro.html
@@ -390,7 +390,7 @@ <h2 class="accordion-header" id="flush-headingTwelve">
       </div>
       <hr></nav><main id="main-content" class="main-content"><div class="container lesson-content">
         <h1>Introduction to R and RStudio</h1>
-        <p>Last updated on 2024-07-02 |
+        <p>Last updated on 2024-08-06 |
 
         <a href="https://github.com/UCL/ClinicianCoders/edit/main/episodes/01-rstudio-intro.Rmd" class="external-link">Edit this page <i aria-hidden="true" data-feather="edit"></i></a></p>
 
@@ -1109,7 +1109,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
     }
     else all.names
 }
-&lt;bytecode: 0x561d3e951d80&gt;
+&lt;bytecode: 0x559ed2a8ed80&gt;
 &lt;environment: namespace:base&gt;</code></pre>
 </div>
 <p>What’s going on here?</p>
@@ -1466,7 +1466,7 @@ <h3 class="callout-title">Key Points<a class="anchor" aria-label="anchor" href="
   "url": "https://UCL.github.io/ClinicianCoders/01-rstudio-intro.html",
   "identifier": "https://UCL.github.io/ClinicianCoders/01-rstudio-intro.html",
   "dateCreated": "2023-10-26",
-  "dateModified": "2024-07-02",
+  "dateModified": "2024-08-06",
   "datePublished": "2024-08-06"
 }
 
diff --git a/02-project-intro.html b/02-project-intro.html
index 334b8c801..47f083584 100644
--- a/02-project-intro.html
+++ b/02-project-intro.html
@@ -381,7 +381,7 @@ <h2 class="accordion-header" id="flush-headingTwelve">
       </div>
       <hr></nav><main id="main-content" class="main-content"><div class="container lesson-content">
         <h1>Project Management With RStudio</h1>
-        <p>Last updated on 2024-07-02 |
+        <p>Last updated on 2024-08-06 |
 
         <a href="https://github.com/UCL/ClinicianCoders/edit/main/episodes/02-project-intro.Rmd" class="external-link">Edit this page <i aria-hidden="true" data-feather="edit"></i></a></p>
 
@@ -629,7 +629,7 @@ <h3 class="code-label">SH<i aria-hidden="true" data-feather="chevron-left"></i><
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="output" tabindex="0"><code>-rw-r--r-- 1 runner docker 80K Jul  2 11:37 data/gapminder_data.csv</code></pre>
+<pre class="output" tabindex="0"><code>-rw-r--r-- 1 runner docker 80K Aug  6 12:20 data/gapminder_data.csv</code></pre>
 </div>
 <p>The file size is 80K.</p>
 <div class="codewrapper sourceCode" id="cb3">
@@ -815,7 +815,7 @@ <h3 class="callout-title">Key Points<a class="anchor" aria-label="anchor" href="
   "url": "https://UCL.github.io/ClinicianCoders/02-project-intro.html",
   "identifier": "https://UCL.github.io/ClinicianCoders/02-project-intro.html",
   "dateCreated": "2023-10-26",
-  "dateModified": "2024-07-02",
+  "dateModified": "2024-08-06",
   "datePublished": "2024-08-06"
 }
 
diff --git a/03-seeking-help.html b/03-seeking-help.html
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@@ -385,7 +385,7 @@ <h2 class="accordion-header" id="flush-headingTwelve">
       </div>
       <hr></nav><main id="main-content" class="main-content"><div class="container lesson-content">
         <h1>Seeking Help</h1>
-        <p>Last updated on 2024-07-02 |
+        <p>Last updated on 2024-08-06 |
 
         <a href="https://github.com/UCL/ClinicianCoders/edit/main/episodes/03-seeking-help.Rmd" class="external-link">Edit this page <i aria-hidden="true" data-feather="edit"></i></a></p>
 
@@ -594,8 +594,8 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 [1] stats     graphics  grDevices utils     datasets  methods   base
 
 loaded via a namespace (and not attached):
-[1] compiler_4.4.1  tools_4.4.1     yaml_2.3.8      knitr_1.47
-[5] xfun_0.45       renv_1.0.7      evaluate_0.24.0</code></pre>
+[1] compiler_4.4.1  tools_4.4.1     yaml_2.3.10     knitr_1.48
+[5] xfun_0.46       renv_1.0.7      evaluate_0.24.0</code></pre>
 </div>
 <p>Will print out your current version of R, as well as any packages you
 have loaded. This can be useful for others to help reproduce and debug
@@ -628,7 +628,7 @@ <h4 class="accordion-header" id="headingSolution1">
   Solution to Challenge 1
   </h4>
 </button>
-<div id="collapseSolution1" class="accordion-collapse collapse" data-bs-parent="#accordionSolution1" aria-labelledby="headingSolution1">
+<div id="collapseSolution1" class="accordion-collapse collapse" aria-labelledby="headingSolution1" data-bs-parent="#accordionSolution1">
 <div class="accordion-body">
 <p>The <code>c()</code> function creates a vector, in which all elements
 are of the same type. In the first case, the elements are numeric, in
@@ -659,7 +659,7 @@ <h4 class="accordion-header" id="headingSolution2">
   Solution to Challenge 2
   </h4>
 </button>
-<div id="collapseSolution2" class="accordion-collapse collapse" data-bs-parent="#accordionSolution2" aria-labelledby="headingSolution2">
+<div id="collapseSolution2" class="accordion-collapse collapse" aria-labelledby="headingSolution2" data-bs-parent="#accordionSolution2">
 <div class="accordion-body">
 <p>To look at the help for the <code>paste()</code> function, use:</p>
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@@ -769,7 +769,7 @@ <h4 class="accordion-header" id="headingSolution3">
   Solution to Challenge 3
   </h4>
 </button>
-<div id="collapseSolution3" class="accordion-collapse collapse" data-bs-parent="#accordionSolution3" aria-labelledby="headingSolution3">
+<div id="collapseSolution3" class="accordion-collapse collapse" aria-labelledby="headingSolution3" data-bs-parent="#accordionSolution3">
 <div class="accordion-body">
 <p>The standard R function for reading tab-delimited files with a period
 decimal separator is read.delim(). You can also do this with
@@ -857,7 +857,7 @@ <h3 class="callout-title">Key Points<a class="anchor" aria-label="anchor" href="
   "url": "https://UCL.github.io/ClinicianCoders/03-seeking-help.html",
   "identifier": "https://UCL.github.io/ClinicianCoders/03-seeking-help.html",
   "dateCreated": "2023-10-26",
-  "dateModified": "2024-07-02",
+  "dateModified": "2024-08-06",
   "datePublished": "2024-08-06"
 }
 
diff --git a/04-data-structures-part1.html b/04-data-structures-part1.html
index b3b4bb388..7309c4a5b 100644
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@@ -380,7 +380,7 @@ <h2 class="accordion-header" id="flush-headingTwelve">
       </div>
       <hr></nav><main id="main-content" class="main-content"><div class="container lesson-content">
         <h1>Data Structures</h1>
-        <p>Last updated on 2024-07-02 |
+        <p>Last updated on 2024-08-06 |
 
         <a href="https://github.com/UCL/ClinicianCoders/edit/main/episodes/04-data-structures-part1.Rmd" class="external-link">Edit this page <i aria-hidden="true" data-feather="edit"></i></a></p>
 
@@ -848,7 +848,7 @@ <h4 class="accordion-header" id="headingSolution1">
   Discussion 1
   </h4>
 </button>
-<div id="collapseSolution1" class="accordion-collapse collapse" aria-labelledby="headingSolution1" data-bs-parent="#accordionSolution1">
+<div id="collapseSolution1" class="accordion-collapse collapse" data-bs-parent="#accordionSolution1" aria-labelledby="headingSolution1">
 <div class="accordion-body">
 <p>By keeping everything in a column the same, we allow ourselves to
 make simple assumptions about our data; if you can interpret one entry
@@ -1075,7 +1075,7 @@ <h4 class="accordion-header" id="headingSolution2">
   Tip 1.1
   </h4>
 </button>
-<div id="collapseSolution2" class="accordion-collapse collapse" aria-labelledby="headingSolution2" data-bs-parent="#accordionSolution2">
+<div id="collapseSolution2" class="accordion-collapse collapse" data-bs-parent="#accordionSolution2" aria-labelledby="headingSolution2">
 <div class="accordion-body">
 <p>Show the content of any variable by typing its name.</p>
 <div class="section level3">
@@ -1109,7 +1109,7 @@ <h4 class="accordion-header" id="headingSolution3">
   Tip 1.2
   </h4>
 </button>
-<div id="collapseSolution3" class="accordion-collapse collapse" aria-labelledby="headingSolution3" data-bs-parent="#accordionSolution3">
+<div id="collapseSolution3" class="accordion-collapse collapse" data-bs-parent="#accordionSolution3" aria-labelledby="headingSolution3">
 <div class="accordion-body">
 <p>In the chapter “Data types” we saw two functions that can show data
 types. One printed just a single word, the data type name. The other
@@ -1150,7 +1150,7 @@ <h4 class="accordion-header" id="headingSolution4">
   Tip 1.3
   </h4>
 </button>
-<div id="collapseSolution4" class="accordion-collapse collapse" aria-labelledby="headingSolution4" data-bs-parent="#accordionSolution4">
+<div id="collapseSolution4" class="accordion-collapse collapse" data-bs-parent="#accordionSolution4" aria-labelledby="headingSolution4">
 <div class="accordion-body">
 <p>Scroll up to the section about the <a href="#the-type-hierarchy">type
 hierarchy</a> to review the available data types</p>
@@ -1165,7 +1165,7 @@ <h4 class="accordion-header" id="headingSolution5">
   Solution to Challenge 1.3
   </h4>
 </button>
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 <div class="accordion-body">
 <ul><li>Weight is expressed on a continuous scale (real numbers). The R data
 type for this is “double” (also known as “numeric”).</li>
@@ -1199,7 +1199,7 @@ <h4 class="accordion-header" id="headingSolution6">
   Tip 1.4
   </h4>
 </button>
-<div id="collapseSolution6" class="accordion-collapse collapse" aria-labelledby="headingSolution6" data-bs-parent="#accordionSolution6">
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 <p>Revisit the hierarchy of data types when two different data types are
 combined.</p>
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   Tip 1.5
   </h4>
 </button>
-<div id="collapseSolution7" class="accordion-collapse collapse" aria-labelledby="headingSolution7" data-bs-parent="#accordionSolution7">
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 <div class="accordion-body">
 <p>The functions to convert data types start with <code>as.</code>. You
 can look for the function further up in the manuscript or use the
@@ -1431,7 +1431,7 @@ <h4 class="accordion-header" id="headingSolution8">
   Solution to Challenge 2
   </h4>
 </button>
-<div id="collapseSolution8" class="accordion-collapse collapse" aria-labelledby="headingSolution8" data-bs-parent="#accordionSolution8">
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 <div class="accordion-body">
 <div class="codewrapper sourceCode" id="cb92">
 <h3 class="code-label">R<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -1657,7 +1657,7 @@ <h4 class="accordion-header" id="headingSolution9">
   Solution to Challenge 3
   </h4>
 </button>
-<div id="collapseSolution9" class="accordion-collapse collapse" aria-labelledby="headingSolution9" data-bs-parent="#accordionSolution9">
+<div id="collapseSolution9" class="accordion-collapse collapse" data-bs-parent="#accordionSolution9" aria-labelledby="headingSolution9">
 <div class="accordion-body">
 <p>You get the names of an object by wrapping the object name inside
 <code>names(...)</code>. Similarly, you get the data type of the names
@@ -1702,7 +1702,7 @@ <h4 class="accordion-header" id="headingSolution10">
   Solution to Challenge 4
   </h4>
 </button>
-<div id="collapseSolution10" class="accordion-collapse collapse" aria-labelledby="headingSolution10" data-bs-parent="#accordionSolution10">
+<div id="collapseSolution10" class="accordion-collapse collapse" data-bs-parent="#accordionSolution10" aria-labelledby="headingSolution10">
 <div class="accordion-body">
 <pre><code><span><span class="va">letter_no</span> <span class="op">&lt;-</span> <span class="fl">1</span><span class="op">:</span><span class="fl">26</span>   <span class="co"># or seq(1,26)</span></span>
 <span><span class="fu">names</span><span class="op">(</span><span class="va">letter_no</span><span class="op">)</span> <span class="op">&lt;-</span> <span class="va">LETTERS</span></span>
@@ -1892,7 +1892,7 @@ <h4 class="accordion-header" id="headingSolution11">
   Solution to Challenge 5
   </h4>
 </button>
-<div id="collapseSolution11" class="accordion-collapse collapse" aria-labelledby="headingSolution11" data-bs-parent="#accordionSolution11">
+<div id="collapseSolution11" class="accordion-collapse collapse" data-bs-parent="#accordionSolution11" aria-labelledby="headingSolution11">
 <div class="accordion-body">
 <div class="codewrapper sourceCode" id="cb138">
 <h3 class="code-label">R<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -2154,7 +2154,7 @@ <h4 class="accordion-header" id="headingSolution12">
   Solution to Challenge 6
   </h4>
 </button>
-<div id="collapseSolution12" class="accordion-collapse collapse" aria-labelledby="headingSolution12" data-bs-parent="#accordionSolution12">
+<div id="collapseSolution12" class="accordion-collapse collapse" data-bs-parent="#accordionSolution12" aria-labelledby="headingSolution12">
 <div class="accordion-body">
 <p>What do you think will be the result of
 <code>length(matrix_example)</code>?</p>
@@ -2200,7 +2200,7 @@ <h4 class="accordion-header" id="headingSolution13">
   Solution to Challenge 7
   </h4>
 </button>
-<div id="collapseSolution13" class="accordion-collapse collapse" aria-labelledby="headingSolution13" data-bs-parent="#accordionSolution13">
+<div id="collapseSolution13" class="accordion-collapse collapse" data-bs-parent="#accordionSolution13" aria-labelledby="headingSolution13">
 <div class="accordion-body">
 <p>Make another matrix, this time containing the numbers 1:50, with 5
 columns and 10 rows. Did the <code>matrix</code> function fill your
@@ -2242,7 +2242,7 @@ <h4 class="accordion-header" id="headingSolution14">
   Solution to Challenge 8
   </h4>
 </button>
-<div id="collapseSolution14" class="accordion-collapse collapse" aria-labelledby="headingSolution14" data-bs-parent="#accordionSolution14">
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@@ -2294,7 +2294,7 @@ <h4 class="accordion-header" id="headingSolution15">
   Solution to Challenge 9
   </h4>
 </button>
-<div id="collapseSolution15" class="accordion-collapse collapse" aria-labelledby="headingSolution15" data-bs-parent="#accordionSolution15">
+<div id="collapseSolution15" class="accordion-collapse collapse" data-bs-parent="#accordionSolution15" aria-labelledby="headingSolution15">
 <div class="accordion-body">
 <p>Consider the R output of the matrix below:</p>
 <div class="codewrapper">
@@ -2393,7 +2393,7 @@ <h3 class="callout-title">Key Points<a class="anchor" aria-label="anchor" href="
   "url": "https://UCL.github.io/ClinicianCoders/04-data-structures-part1.html",
   "identifier": "https://UCL.github.io/ClinicianCoders/04-data-structures-part1.html",
   "dateCreated": "2023-10-26",
-  "dateModified": "2024-07-02",
+  "dateModified": "2024-08-06",
   "datePublished": "2024-08-06"
 }
 
diff --git a/05-data-structures-part2.html b/05-data-structures-part2.html
index 6e4256ac5..622f94101 100644
--- a/05-data-structures-part2.html
+++ b/05-data-structures-part2.html
@@ -383,7 +383,7 @@ <h2 class="accordion-header" id="flush-headingTwelve">
       </div>
       <hr></nav><main id="main-content" class="main-content"><div class="container lesson-content">
         <h1>Exploring Data Frames</h1>
-        <p>Last updated on 2024-07-02 |
+        <p>Last updated on 2024-08-06 |
 
         <a href="https://github.com/UCL/ClinicianCoders/edit/main/episodes/05-data-structures-part2.Rmd" class="external-link">Edit this page <i aria-hidden="true" data-feather="edit"></i></a></p>
 
@@ -1184,7 +1184,7 @@ <h3 class="callout-title">Key Points<a class="anchor" aria-label="anchor" href="
   "url": "https://UCL.github.io/ClinicianCoders/05-data-structures-part2.html",
   "identifier": "https://UCL.github.io/ClinicianCoders/05-data-structures-part2.html",
   "dateCreated": "2023-10-26",
-  "dateModified": "2024-07-02",
+  "dateModified": "2024-08-06",
   "datePublished": "2024-08-06"
 }
 
diff --git a/06-data-subsetting.html b/06-data-subsetting.html
index f5d9747ff..b4a327283 100644
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+++ b/06-data-subsetting.html
@@ -388,7 +388,7 @@ <h2 class="accordion-header" id="flush-headingTwelve">
       </div>
       <hr></nav><main id="main-content" class="main-content"><div class="container lesson-content">
         <h1>Subsetting Data</h1>
-        <p>Last updated on 2024-07-02 |
+        <p>Last updated on 2024-08-06 |
 
         <a href="https://github.com/UCL/ClinicianCoders/edit/main/episodes/06-data-subsetting.Rmd" class="external-link">Edit this page <i aria-hidden="true" data-feather="edit"></i></a></p>
 
@@ -726,7 +726,7 @@ <h4 class="accordion-header" id="headingSolution1">
   Solution to challenge 1
   </h4>
 </button>
-<div id="collapseSolution1" class="accordion-collapse collapse" data-bs-parent="#accordionSolution1" aria-labelledby="headingSolution1">
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   Solution to challenge 2
   </h4>
 </button>
-<div id="collapseSolution2" class="accordion-collapse collapse" data-bs-parent="#accordionSolution2" aria-labelledby="headingSolution2">
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@@ -1170,7 +1170,7 @@ <h4 class="accordion-header" id="headingSolution3">
   Solution to challenge 3
   </h4>
 </button>
-<div id="collapseSolution3" class="accordion-collapse collapse" data-bs-parent="#accordionSolution3" aria-labelledby="headingSolution3">
+<div id="collapseSolution3" class="accordion-collapse collapse" aria-labelledby="headingSolution3" data-bs-parent="#accordionSolution3">
 <div class="accordion-body">
 <ul><li>The <strong>wrong</strong> way to do this problem is
 <code>countries==seAsia</code>. This gives a warning
@@ -1453,7 +1453,7 @@ <h4 class="accordion-header" id="headingSolution4">
   Solution to challenge 4
   </h4>
 </button>
-<div id="collapseSolution4" class="accordion-collapse collapse" data-bs-parent="#accordionSolution4" aria-labelledby="headingSolution4">
+<div id="collapseSolution4" class="accordion-collapse collapse" aria-labelledby="headingSolution4" data-bs-parent="#accordionSolution4">
 <div class="accordion-body">
 <p>D</p>
 </div>
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   Solution to challenge 5
   </h4>
 </button>
-<div id="collapseSolution5" class="accordion-collapse collapse" data-bs-parent="#accordionSolution5" aria-labelledby="headingSolution5">
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 <div class="accordion-body">
 <div class="codewrapper sourceCode" id="cb115">
 <h3 class="code-label">R<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -1666,7 +1666,7 @@ <h4 class="accordion-header" id="headingSolution6">
   Solution to challenge 6
   </h4>
 </button>
-<div id="collapseSolution6" class="accordion-collapse collapse" data-bs-parent="#accordionSolution6" aria-labelledby="headingSolution6">
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 <div class="accordion-body">
 <div class="codewrapper sourceCode" id="cb122">
 <h3 class="code-label">R<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -1822,7 +1822,7 @@ <h4 class="accordion-header" id="headingSolution7">
   Solution to challenge 7
   </h4>
 </button>
-<div id="collapseSolution7" class="accordion-collapse collapse" data-bs-parent="#accordionSolution7" aria-labelledby="headingSolution7">
+<div id="collapseSolution7" class="accordion-collapse collapse" aria-labelledby="headingSolution7" data-bs-parent="#accordionSolution7">
 <div class="accordion-body">
 <p>Fix each of the following common data frame subsetting errors:</p>
 <ol style="list-style-type: decimal"><li>Extract observations collected for the year 1957</li>
@@ -1896,7 +1896,7 @@ <h4 class="accordion-header" id="headingSolution8">
   Solution to challenge 8
   </h4>
 </button>
-<div id="collapseSolution8" class="accordion-collapse collapse" data-bs-parent="#accordionSolution8" aria-labelledby="headingSolution8">
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 <div class="accordion-body">
 <ol style="list-style-type: decimal"><li><p><code>gapminder</code> is a data.frame so needs to be subsetted
 on two dimensions. <code>gapminder[1:20, ]</code> subsets the data to
@@ -1988,7 +1988,7 @@ <h3 class="callout-title">Key Points<a class="anchor" aria-label="anchor" href="
   "url": "https://UCL.github.io/ClinicianCoders/06-data-subsetting.html",
   "identifier": "https://UCL.github.io/ClinicianCoders/06-data-subsetting.html",
   "dateCreated": "2023-10-26",
-  "dateModified": "2024-07-02",
+  "dateModified": "2024-08-06",
   "datePublished": "2024-08-06"
 }
 
diff --git a/08-plot-ggplot2.html b/08-plot-ggplot2.html
index 3fb6e12d2..e1eabf632 100644
--- a/08-plot-ggplot2.html
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@@ -383,7 +383,7 @@ <h2 class="accordion-header" id="flush-headingTwelve">
       </div>
       <hr></nav><main id="main-content" class="main-content"><div class="container lesson-content">
         <h1>Creating Publication-Quality Graphics with ggplot2</h1>
-        <p>Last updated on 2024-07-02 |
+        <p>Last updated on 2024-08-06 |
 
         <a href="https://github.com/UCL/ClinicianCoders/edit/main/episodes/08-plot-ggplot2.Rmd" class="external-link">Edit this page <i aria-hidden="true" data-feather="edit"></i></a></p>
 
@@ -526,7 +526,7 @@ <h4 class="accordion-header" id="headingSolution1">
   Solution to challenge 1
   </h4>
 </button>
-<div id="collapseSolution1" class="accordion-collapse collapse" aria-labelledby="headingSolution1" data-bs-parent="#accordionSolution1">
+<div id="collapseSolution1" class="accordion-collapse collapse" data-bs-parent="#accordionSolution1" aria-labelledby="headingSolution1">
 <div class="accordion-body">
 <p>Here is one possible solution:</p>
 <div class="codewrapper sourceCode" id="cb5">
@@ -567,7 +567,7 @@ <h4 class="accordion-header" id="headingSolution2">
   Solution to challenge 2
   </h4>
 </button>
-<div id="collapseSolution2" class="accordion-collapse collapse" aria-labelledby="headingSolution2" data-bs-parent="#accordionSolution2">
+<div id="collapseSolution2" class="accordion-collapse collapse" data-bs-parent="#accordionSolution2" aria-labelledby="headingSolution2">
 <div class="accordion-body">
 <p>The solution presented below adds <code>color=continent</code> to the
 call of the <code>aes</code> function. The general trend seems to
@@ -678,7 +678,7 @@ <h4 class="accordion-header" id="headingSolution3">
   Solution to challenge 3
   </h4>
 </button>
-<div id="collapseSolution3" class="accordion-collapse collapse" aria-labelledby="headingSolution3" data-bs-parent="#accordionSolution3">
+<div id="collapseSolution3" class="accordion-collapse collapse" data-bs-parent="#accordionSolution3" aria-labelledby="headingSolution3">
 <div class="accordion-body">
 <p>The lines now get drawn over the points!</p>
 <div class="codewrapper sourceCode" id="cb11">
@@ -809,7 +809,7 @@ <h4 class="accordion-header" id="headingSolution4">
   Solution to challenge 4a
   </h4>
 </button>
-<div id="collapseSolution4" class="accordion-collapse collapse" aria-labelledby="headingSolution4" data-bs-parent="#accordionSolution4">
+<div id="collapseSolution4" class="accordion-collapse collapse" data-bs-parent="#accordionSolution4" aria-labelledby="headingSolution4">
 <div class="accordion-body">
 <p>Here a possible solution: Notice that the <code>color</code> argument
 is supplied outside of the <code>aes()</code> function. This means that
@@ -853,7 +853,7 @@ <h4 class="accordion-header" id="headingSolution5">
   Solution to challenge 4b
   </h4>
 </button>
-<div id="collapseSolution5" class="accordion-collapse collapse" aria-labelledby="headingSolution5" data-bs-parent="#accordionSolution5">
+<div id="collapseSolution5" class="accordion-collapse collapse" data-bs-parent="#accordionSolution5" aria-labelledby="headingSolution5">
 <div class="accordion-body">
 <p>Here is a possible solution: Notice that supplying the
 <code>color</code> argument inside the <code>aes()</code> functions
@@ -1007,7 +1007,7 @@ <h4 class="accordion-header" id="headingSolution6">
   Solution to Challenge 5
   </h4>
 </button>
-<div id="collapseSolution6" class="accordion-collapse collapse" aria-labelledby="headingSolution6" data-bs-parent="#accordionSolution6">
+<div id="collapseSolution6" class="accordion-collapse collapse" data-bs-parent="#accordionSolution6" aria-labelledby="headingSolution6">
 <div class="accordion-body">
 <p>Here a possible solution: <code>xlab()</code> and <code>ylab()</code>
 set labels for the x and y axes, respectively The axis title, text and
@@ -1100,7 +1100,7 @@ <h3 class="callout-title">Key Points<a class="anchor" aria-label="anchor" href="
   "url": "https://UCL.github.io/ClinicianCoders/08-plot-ggplot2.html",
   "identifier": "https://UCL.github.io/ClinicianCoders/08-plot-ggplot2.html",
   "dateCreated": "2023-10-26",
-  "dateModified": "2024-07-02",
+  "dateModified": "2024-08-06",
   "datePublished": "2024-08-06"
 }
 
diff --git a/11-writing-data.html b/11-writing-data.html
index 0d4751ab2..272081ce3 100644
--- a/11-writing-data.html
+++ b/11-writing-data.html
@@ -380,7 +380,7 @@ <h2 class="accordion-header" id="flush-headingTwelve">
       </div>
       <hr></nav><main id="main-content" class="main-content"><div class="container lesson-content">
         <h1>Writing Data</h1>
-        <p>Last updated on 2024-07-02 |
+        <p>Last updated on 2024-08-06 |
 
         <a href="https://github.com/UCL/ClinicianCoders/edit/main/episodes/11-writing-data.Rmd" class="external-link">Edit this page <i aria-hidden="true" data-feather="edit"></i></a></p>
 
@@ -684,7 +684,7 @@ <h3 class="callout-title">Key Points<a class="anchor" aria-label="anchor" href="
   "url": "https://UCL.github.io/ClinicianCoders/11-writing-data.html",
   "identifier": "https://UCL.github.io/ClinicianCoders/11-writing-data.html",
   "dateCreated": "2023-10-26",
-  "dateModified": "2024-07-02",
+  "dateModified": "2024-08-06",
   "datePublished": "2024-08-06"
 }
 
diff --git a/12-dplyr.html b/12-dplyr.html
index 317d9172d..e3d0fb187 100644
--- a/12-dplyr.html
+++ b/12-dplyr.html
@@ -388,7 +388,7 @@ <h2 class="accordion-header" id="flush-headingTwelve">
       </div>
       <hr></nav><main id="main-content" class="main-content"><div class="container lesson-content">
         <h1>Data Frame Manipulation with dplyr</h1>
-        <p>Last updated on 2024-07-02 |
+        <p>Last updated on 2024-08-06 |
 
         <a href="https://github.com/UCL/ClinicianCoders/edit/main/episodes/12-dplyr.Rmd" class="external-link">Edit this page <i aria-hidden="true" data-feather="edit"></i></a></p>
 
@@ -1241,7 +1241,7 @@ <h3 class="callout-title">Key Points<a class="anchor" aria-label="anchor" href="
   "url": "https://UCL.github.io/ClinicianCoders/12-dplyr.html",
   "identifier": "https://UCL.github.io/ClinicianCoders/12-dplyr.html",
   "dateCreated": "2023-10-26",
-  "dateModified": "2024-07-02",
+  "dateModified": "2024-08-06",
   "datePublished": "2024-08-06"
 }
 
diff --git a/13-tidyr.html b/13-tidyr.html
index 19ea3ef6f..312fdcd9a 100644
--- a/13-tidyr.html
+++ b/13-tidyr.html
@@ -382,7 +382,7 @@ <h2 class="accordion-header" id="flush-headingTwelve">
       </div>
       <hr></nav><main id="main-content" class="main-content"><div class="container lesson-content">
         <h1>Data Frame Manipulation with tidyr</h1>
-        <p>Last updated on 2024-07-02 |
+        <p>Last updated on 2024-08-06 |
 
         <a href="https://github.com/UCL/ClinicianCoders/edit/main/episodes/13-tidyr.Rmd" class="external-link">Edit this page <i aria-hidden="true" data-feather="edit"></i></a></p>
 
@@ -1161,7 +1161,7 @@ <h3 class="callout-title">Key Points<a class="anchor" aria-label="anchor" href="
   "url": "https://UCL.github.io/ClinicianCoders/13-tidyr.html",
   "identifier": "https://UCL.github.io/ClinicianCoders/13-tidyr.html",
   "dateCreated": "2023-10-26",
-  "dateModified": "2024-07-02",
+  "dateModified": "2024-08-06",
   "datePublished": "2024-08-06"
 }
 
diff --git a/14-knitr-markdown.html b/14-knitr-markdown.html
index a6265e664..d0c00ef60 100644
--- a/14-knitr-markdown.html
+++ b/14-knitr-markdown.html
@@ -390,7 +390,7 @@ <h2 class="accordion-header" id="flush-headingTwelve">
       </div>
       <hr></nav><main id="main-content" class="main-content"><div class="container lesson-content">
         <h1>Producing Reports With knitr</h1>
-        <p>Last updated on 2024-07-02 |
+        <p>Last updated on 2024-08-06 |
 
         <a href="https://github.com/UCL/ClinicianCoders/edit/main/episodes/14-knitr-markdown.Rmd" class="external-link">Edit this page <i aria-hidden="true" data-feather="edit"></i></a></p>
 
@@ -572,7 +572,7 @@ <h4 class="accordion-header" id="headingSolution1">
   Solution to Challenge 1
   </h4>
 </button>
-<div id="collapseSolution1" class="accordion-collapse collapse" aria-labelledby="headingSolution1" data-bs-parent="#accordionSolution1">
+<div id="collapseSolution1" class="accordion-collapse collapse" data-bs-parent="#accordionSolution1" aria-labelledby="headingSolution1">
 <div class="accordion-body">
 <p>In RStudio, select File &gt; New file &gt; R Markdown…</p>
 <p>Delete the placeholder text and add the following:</p>
@@ -651,7 +651,7 @@ <h4 class="accordion-header" id="headingSolution2">
   Solution to Challenge 2
   </h4>
 </button>
-<div id="collapseSolution2" class="accordion-collapse collapse" aria-labelledby="headingSolution2" data-bs-parent="#accordionSolution2">
+<div id="collapseSolution2" class="accordion-collapse collapse" data-bs-parent="#accordionSolution2" aria-labelledby="headingSolution2">
 <div class="accordion-body">
 <pre>
 ```{r load-ggplot2}
@@ -739,7 +739,7 @@ <h4 class="accordion-header" id="headingSolution3">
   Solution to Challenge 3
   </h4>
 </button>
-<div id="collapseSolution3" class="accordion-collapse collapse" aria-labelledby="headingSolution3" data-bs-parent="#accordionSolution3">
+<div id="collapseSolution3" class="accordion-collapse collapse" data-bs-parent="#accordionSolution3" aria-labelledby="headingSolution3">
 <div class="accordion-body">
 <pre>
 ```{r echo = FALSE, fig.width = 3}
@@ -789,7 +789,7 @@ <h4 class="accordion-header" id="headingSolution4">
   Solution to Challenge 4
   </h4>
 </button>
-<div id="collapseSolution4" class="accordion-collapse collapse" aria-labelledby="headingSolution4" data-bs-parent="#accordionSolution4">
+<div id="collapseSolution4" class="accordion-collapse collapse" data-bs-parent="#accordionSolution4" aria-labelledby="headingSolution4">
 <div class="accordion-body">
 <p>Here’s some inline code to determine that 2 + 2 = <code>4</code>.</p>
 </div>
@@ -936,7 +936,7 @@ <h3 class="callout-title">Key Points<a class="anchor" aria-label="anchor" href="
   "url": "https://UCL.github.io/ClinicianCoders/14-knitr-markdown.html",
   "identifier": "https://UCL.github.io/ClinicianCoders/14-knitr-markdown.html",
   "dateCreated": "2023-10-26",
-  "dateModified": "2024-07-02",
+  "dateModified": "2024-08-06",
   "datePublished": "2024-08-06"
 }
 
diff --git a/15-wrap-up.html b/15-wrap-up.html
index 6911a5b1b..ec5e2fbcd 100644
--- a/15-wrap-up.html
+++ b/15-wrap-up.html
@@ -386,7 +386,7 @@ <h2 class="accordion-header" id="flush-headingTwelve">
       </div>
       <hr></nav><main id="main-content" class="main-content"><div class="container lesson-content">
         <h1>Writing Good Software</h1>
-        <p>Last updated on 2024-07-02 |
+        <p>Last updated on 2024-08-06 |
 
         <a href="https://github.com/UCL/ClinicianCoders/edit/main/episodes/15-wrap-up.Rmd" class="external-link">Edit this page <i aria-hidden="true" data-feather="edit"></i></a></p>
 
@@ -583,7 +583,7 @@ <h3 class="callout-title">Key Points<a class="anchor" aria-label="anchor" href="
   "url": "https://UCL.github.io/ClinicianCoders/15-wrap-up.html",
   "identifier": "https://UCL.github.io/ClinicianCoders/15-wrap-up.html",
   "dateCreated": "2023-10-26",
-  "dateModified": "2024-07-02",
+  "dateModified": "2024-08-06",
   "datePublished": "2024-08-06"
 }
 
diff --git a/CODE_OF_CONDUCT.html b/CODE_OF_CONDUCT.html
index 60571275f..81c88e4ca 100644
--- a/CODE_OF_CONDUCT.html
+++ b/CODE_OF_CONDUCT.html
@@ -368,7 +368,7 @@ <h2 class="accordion-header" id="flush-headingTwelve">
       </div>
       <hr></nav><main id="main-content" class="main-content"><div class="container lesson-content">
         <h1>Contributor Code of Conduct</h1>
-        <p>Last updated on 2024-07-02 |
+        <p>Last updated on 2024-08-06 |
 
         <a href="https://github.com/UCL/ClinicianCoders/edit/main/CODE_OF_CONDUCT.md" class="external-link">Edit this page <i aria-hidden="true" data-feather="edit"></i></a></p>
 
@@ -447,7 +447,7 @@ <h1>Contributor Code of Conduct</h1>
   "url": "https://UCL.github.io/ClinicianCoders/CODE_OF_CONDUCT.html",
   "identifier": "https://UCL.github.io/ClinicianCoders/CODE_OF_CONDUCT.html",
   "dateCreated": "2023-10-26",
-  "dateModified": "2024-07-02",
+  "dateModified": "2024-08-06",
   "datePublished": "2024-08-06"
 }
 
diff --git a/LICENSE.html b/LICENSE.html
index 871a9a859..6234807af 100644
--- a/LICENSE.html
+++ b/LICENSE.html
@@ -368,7 +368,7 @@ <h2 class="accordion-header" id="flush-headingTwelve">
       </div>
       <hr></nav><main id="main-content" class="main-content"><div class="container lesson-content">
         <h1>Licenses</h1>
-        <p>Last updated on 2024-07-02 |
+        <p>Last updated on 2024-08-06 |
 
         <a href="https://github.com/UCL/ClinicianCoders/edit/main/LICENSE.md" class="external-link">Edit this page <i aria-hidden="true" data-feather="edit"></i></a></p>
 
@@ -498,7 +498,7 @@ <h1>Licenses</h1>
   "url": "https://UCL.github.io/ClinicianCoders/LICENSE.html",
   "identifier": "https://UCL.github.io/ClinicianCoders/LICENSE.html",
   "dateCreated": "2023-10-26",
-  "dateModified": "2024-07-02",
+  "dateModified": "2024-08-06",
   "datePublished": "2024-08-06"
 }
 
diff --git a/aio.html b/aio.html
index 8947e021e..8e65f110d 100644
--- a/aio.html
+++ b/aio.html
@@ -445,7 +445,7 @@ <h2 class="accordion-header" id="flush-headingTwelve">
         
 <section id="aio-01-rstudio-intro"><p>Content from <a href="01-rstudio-intro.html">Introduction to R and RStudio</a></p>
 <hr>
-<p>Last updated on 2024-07-02 |
+<p>Last updated on 2024-08-06 |
 
         <a href="https://github.com/UCL/ClinicianCoders/edit/main/episodes/01-rstudio-intro.Rmd" class="external-link">Edit this page <i aria-hidden="true" data-feather="edit"></i></a></p>
 <div class="text-end">
@@ -1201,7 +1201,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
     }
     else all.names
 }
-&lt;bytecode: 0x561d3e951d80&gt;
+&lt;bytecode: 0x559ed2a8ed80&gt;
 &lt;environment: namespace:base&gt;</code></pre>
 </div>
 <p>What’s going on here?</p>
@@ -1508,7 +1508,7 @@ <h3 class="callout-title">Key Points<a class="anchor" aria-label="anchor" href="
 </div>
 </section></section><section id="aio-02-project-intro"><p>Content from <a href="02-project-intro.html">Project Management With RStudio</a></p>
 <hr>
-<p>Last updated on 2024-07-02 |
+<p>Last updated on 2024-08-06 |
 
         <a href="https://github.com/UCL/ClinicianCoders/edit/main/episodes/02-project-intro.Rmd" class="external-link">Edit this page <i aria-hidden="true" data-feather="edit"></i></a></p>
 <div class="text-end">
@@ -1778,7 +1778,7 @@ <h3 class="code-label">SH<i aria-hidden="true" data-feather="chevron-left"></i><
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="output" tabindex="0"><code>-rw-r--r-- 1 runner docker 80K Jul  2 11:37 data/gapminder_data.csv</code></pre>
+<pre class="output" tabindex="0"><code>-rw-r--r-- 1 runner docker 80K Aug  6 12:20 data/gapminder_data.csv</code></pre>
 </div>
 <p>The file size is 80K.</p>
 <div class="codewrapper sourceCode" id="cb3">
@@ -1916,7 +1916,7 @@ <h3 class="callout-title">Key Points<a class="anchor" aria-label="anchor" href="
 </div>
 </section></section><section id="aio-03-seeking-help"><p>Content from <a href="03-seeking-help.html">Seeking Help</a></p>
 <hr>
-<p>Last updated on 2024-07-02 |
+<p>Last updated on 2024-08-06 |
 
         <a href="https://github.com/UCL/ClinicianCoders/edit/main/episodes/03-seeking-help.Rmd" class="external-link">Edit this page <i aria-hidden="true" data-feather="edit"></i></a></p>
 <div class="text-end">
@@ -2137,8 +2137,8 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 [1] stats     graphics  grDevices utils     datasets  methods   base
 
 loaded via a namespace (and not attached):
-[1] compiler_4.4.1  tools_4.4.1     yaml_2.3.8      knitr_1.47
-[5] xfun_0.45       renv_1.0.7      evaluate_0.24.0</code></pre>
+[1] compiler_4.4.1  tools_4.4.1     yaml_2.3.10     knitr_1.48
+[5] xfun_0.46       renv_1.0.7      evaluate_0.24.0</code></pre>
 </div>
 <p>Will print out your current version of R, as well as any packages you
 have loaded. This can be useful for others to help reproduce and debug
@@ -2171,7 +2171,7 @@ <h4 class="accordion-header" id="headingSolution1">
   Solution to Challenge 1
   </h4>
 </button>
-<div id="collapseSolution1" class="accordion-collapse collapse" data-bs-parent="#accordionSolution1" aria-labelledby="headingSolution1">
+<div id="collapseSolution1" class="accordion-collapse collapse" aria-labelledby="headingSolution1" data-bs-parent="#accordionSolution1">
 <div class="accordion-body">
 <p>The <code>c()</code> function creates a vector, in which all elements
 are of the same type. In the first case, the elements are numeric, in
@@ -2202,7 +2202,7 @@ <h4 class="accordion-header" id="headingSolution2">
   Solution to Challenge 2
   </h4>
 </button>
-<div id="collapseSolution2" class="accordion-collapse collapse" data-bs-parent="#accordionSolution2" aria-labelledby="headingSolution2">
+<div id="collapseSolution2" class="accordion-collapse collapse" aria-labelledby="headingSolution2" data-bs-parent="#accordionSolution2">
 <div class="accordion-body">
 <p>To look at the help for the <code>paste()</code> function, use:</p>
 <div class="codewrapper sourceCode" id="cb11">
@@ -2312,7 +2312,7 @@ <h4 class="accordion-header" id="headingSolution3">
   Solution to Challenge 3
   </h4>
 </button>
-<div id="collapseSolution3" class="accordion-collapse collapse" data-bs-parent="#accordionSolution3" aria-labelledby="headingSolution3">
+<div id="collapseSolution3" class="accordion-collapse collapse" aria-labelledby="headingSolution3" data-bs-parent="#accordionSolution3">
 <div class="accordion-body">
 <p>The standard R function for reading tab-delimited files with a period
 decimal separator is read.delim(). You can also do this with
@@ -2350,7 +2350,7 @@ <h3 class="callout-title">Key Points<a class="anchor" aria-label="anchor" href="
 </div>
 </section></section><section id="aio-04-data-structures-part1"><p>Content from <a href="04-data-structures-part1.html">Data Structures</a></p>
 <hr>
-<p>Last updated on 2024-07-02 |
+<p>Last updated on 2024-08-06 |
 
         <a href="https://github.com/UCL/ClinicianCoders/edit/main/episodes/04-data-structures-part1.Rmd" class="external-link">Edit this page <i aria-hidden="true" data-feather="edit"></i></a></p>
 <div class="text-end">
@@ -2820,7 +2820,7 @@ <h4 class="accordion-header" id="headingSolution1">
   Discussion 1
   </h4>
 </button>
-<div id="collapseSolution1" class="accordion-collapse collapse" aria-labelledby="headingSolution1" data-bs-parent="#accordionSolution1">
+<div id="collapseSolution1" class="accordion-collapse collapse" data-bs-parent="#accordionSolution1" aria-labelledby="headingSolution1">
 <div class="accordion-body">
 <p>By keeping everything in a column the same, we allow ourselves to
 make simple assumptions about our data; if you can interpret one entry
@@ -3052,7 +3052,7 @@ <h4 class="accordion-header" id="headingSolution2">
   Tip 1.1
   </h4>
 </button>
-<div id="collapseSolution2" class="accordion-collapse collapse" aria-labelledby="headingSolution2" data-bs-parent="#accordionSolution2">
+<div id="collapseSolution2" class="accordion-collapse collapse" data-bs-parent="#accordionSolution2" aria-labelledby="headingSolution2">
 <div class="accordion-body">
 <p>Show the content of any variable by typing its name.</p>
 <div class="section level3">
@@ -3087,7 +3087,7 @@ <h4 class="accordion-header" id="headingSolution3">
   Tip 1.2
   </h4>
 </button>
-<div id="collapseSolution3" class="accordion-collapse collapse" aria-labelledby="headingSolution3" data-bs-parent="#accordionSolution3">
+<div id="collapseSolution3" class="accordion-collapse collapse" data-bs-parent="#accordionSolution3" aria-labelledby="headingSolution3">
 <div class="accordion-body">
 <p>In the chapter “Data types” we saw two functions that can show data
 types. One printed just a single word, the data type name. The other
@@ -3131,7 +3131,7 @@ <h4 class="accordion-header" id="headingSolution4">
   Tip 1.3
   </h4>
 </button>
-<div id="collapseSolution4" class="accordion-collapse collapse" aria-labelledby="headingSolution4" data-bs-parent="#accordionSolution4">
+<div id="collapseSolution4" class="accordion-collapse collapse" data-bs-parent="#accordionSolution4" aria-labelledby="headingSolution4">
 <div class="accordion-body">
 <p>Scroll up to the section about the <a href="#the-type-hierarchy">type
 hierarchy</a> to review the available data types</p>
@@ -3146,7 +3146,7 @@ <h4 class="accordion-header" id="headingSolution5">
   Solution to Challenge 1.3
   </h4>
 </button>
-<div id="collapseSolution5" class="accordion-collapse collapse" aria-labelledby="headingSolution5" data-bs-parent="#accordionSolution5">
+<div id="collapseSolution5" class="accordion-collapse collapse" data-bs-parent="#accordionSolution5" aria-labelledby="headingSolution5">
 <div class="accordion-body">
 <ul>
 <li>Weight is expressed on a continuous scale (real numbers). The R data
@@ -3182,7 +3182,7 @@ <h4 class="accordion-header" id="headingSolution6">
   Tip 1.4
   </h4>
 </button>
-<div id="collapseSolution6" class="accordion-collapse collapse" aria-labelledby="headingSolution6" data-bs-parent="#accordionSolution6">
+<div id="collapseSolution6" class="accordion-collapse collapse" data-bs-parent="#accordionSolution6" aria-labelledby="headingSolution6">
 <div class="accordion-body">
 <p>Revisit the hierarchy of data types when two different data types are
 combined.</p>
@@ -3223,7 +3223,7 @@ <h4 class="accordion-header" id="headingSolution7">
   Tip 1.5
   </h4>
 </button>
-<div id="collapseSolution7" class="accordion-collapse collapse" aria-labelledby="headingSolution7" data-bs-parent="#accordionSolution7">
+<div id="collapseSolution7" class="accordion-collapse collapse" data-bs-parent="#accordionSolution7" aria-labelledby="headingSolution7">
 <div class="accordion-body">
 <p>The functions to convert data types start with <code>as.</code>. You
 can look for the function further up in the manuscript or use the
@@ -3416,7 +3416,7 @@ <h4 class="accordion-header" id="headingSolution8">
   Solution to Challenge 2
   </h4>
 </button>
-<div id="collapseSolution8" class="accordion-collapse collapse" aria-labelledby="headingSolution8" data-bs-parent="#accordionSolution8">
+<div id="collapseSolution8" class="accordion-collapse collapse" data-bs-parent="#accordionSolution8" aria-labelledby="headingSolution8">
 <div class="accordion-body">
 <div class="codewrapper sourceCode" id="cb92">
 <h3 class="code-label">R<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -3649,7 +3649,7 @@ <h4 class="accordion-header" id="headingSolution9">
   Solution to Challenge 3
   </h4>
 </button>
-<div id="collapseSolution9" class="accordion-collapse collapse" aria-labelledby="headingSolution9" data-bs-parent="#accordionSolution9">
+<div id="collapseSolution9" class="accordion-collapse collapse" data-bs-parent="#accordionSolution9" aria-labelledby="headingSolution9">
 <div class="accordion-body">
 <p>You get the names of an object by wrapping the object name inside
 <code>names(...)</code>. Similarly, you get the data type of the names
@@ -3696,7 +3696,7 @@ <h4 class="accordion-header" id="headingSolution10">
   Solution to Challenge 4
   </h4>
 </button>
-<div id="collapseSolution10" class="accordion-collapse collapse" aria-labelledby="headingSolution10" data-bs-parent="#accordionSolution10">
+<div id="collapseSolution10" class="accordion-collapse collapse" data-bs-parent="#accordionSolution10" aria-labelledby="headingSolution10">
 <div class="accordion-body">
 <pre><code><span><span class="va">letter_no</span> <span class="op">&lt;-</span> <span class="fl">1</span><span class="op">:</span><span class="fl">26</span>   <span class="co"># or seq(1,26)</span></span>
 <span><span class="fu">names</span><span class="op">(</span><span class="va">letter_no</span><span class="op">)</span> <span class="op">&lt;-</span> <span class="va">LETTERS</span></span>
@@ -3890,7 +3890,7 @@ <h4 class="accordion-header" id="headingSolution11">
   Solution to Challenge 5
   </h4>
 </button>
-<div id="collapseSolution11" class="accordion-collapse collapse" aria-labelledby="headingSolution11" data-bs-parent="#accordionSolution11">
+<div id="collapseSolution11" class="accordion-collapse collapse" data-bs-parent="#accordionSolution11" aria-labelledby="headingSolution11">
 <div class="accordion-body">
 <div class="codewrapper sourceCode" id="cb138">
 <h3 class="code-label">R<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -4153,7 +4153,7 @@ <h4 class="accordion-header" id="headingSolution12">
   Solution to Challenge 6
   </h4>
 </button>
-<div id="collapseSolution12" class="accordion-collapse collapse" aria-labelledby="headingSolution12" data-bs-parent="#accordionSolution12">
+<div id="collapseSolution12" class="accordion-collapse collapse" data-bs-parent="#accordionSolution12" aria-labelledby="headingSolution12">
 <div class="accordion-body">
 <p>What do you think will be the result of
 <code>length(matrix_example)</code>?</p>
@@ -4199,7 +4199,7 @@ <h4 class="accordion-header" id="headingSolution13">
   Solution to Challenge 7
   </h4>
 </button>
-<div id="collapseSolution13" class="accordion-collapse collapse" aria-labelledby="headingSolution13" data-bs-parent="#accordionSolution13">
+<div id="collapseSolution13" class="accordion-collapse collapse" data-bs-parent="#accordionSolution13" aria-labelledby="headingSolution13">
 <div class="accordion-body">
 <p>Make another matrix, this time containing the numbers 1:50, with 5
 columns and 10 rows. Did the <code>matrix</code> function fill your
@@ -4243,7 +4243,7 @@ <h4 class="accordion-header" id="headingSolution14">
   Solution to Challenge 8
   </h4>
 </button>
-<div id="collapseSolution14" class="accordion-collapse collapse" aria-labelledby="headingSolution14" data-bs-parent="#accordionSolution14">
+<div id="collapseSolution14" class="accordion-collapse collapse" data-bs-parent="#accordionSolution14" aria-labelledby="headingSolution14">
 <div class="accordion-body">
 <div class="codewrapper sourceCode" id="cb173">
 <h3 class="code-label">R<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -4297,7 +4297,7 @@ <h4 class="accordion-header" id="headingSolution15">
   Solution to Challenge 9
   </h4>
 </button>
-<div id="collapseSolution15" class="accordion-collapse collapse" aria-labelledby="headingSolution15" data-bs-parent="#accordionSolution15">
+<div id="collapseSolution15" class="accordion-collapse collapse" data-bs-parent="#accordionSolution15" aria-labelledby="headingSolution15">
 <div class="accordion-body">
 <p>Consider the R output of the matrix below:</p>
 <div class="codewrapper">
@@ -4342,7 +4342,7 @@ <h3 class="callout-title">Key Points<a class="anchor" aria-label="anchor" href="
 </div>
 </section></section><section id="aio-05-data-structures-part2"><p>Content from <a href="05-data-structures-part2.html">Exploring Data Frames</a></p>
 <hr>
-<p>Last updated on 2024-07-02 |
+<p>Last updated on 2024-08-06 |
 
         <a href="https://github.com/UCL/ClinicianCoders/edit/main/episodes/05-data-structures-part2.Rmd" class="external-link">Edit this page <i aria-hidden="true" data-feather="edit"></i></a></p>
 <div class="text-end">
@@ -5108,7 +5108,7 @@ <h3 class="callout-title">Key Points<a class="anchor" aria-label="anchor" href="
 </div>
 </section></section><section id="aio-06-data-subsetting"><p>Content from <a href="06-data-subsetting.html">Subsetting Data</a></p>
 <hr>
-<p>Last updated on 2024-07-02 |
+<p>Last updated on 2024-08-06 |
 
         <a href="https://github.com/UCL/ClinicianCoders/edit/main/episodes/06-data-subsetting.Rmd" class="external-link">Edit this page <i aria-hidden="true" data-feather="edit"></i></a></p>
 <div class="text-end">
@@ -5448,7 +5448,7 @@ <h4 class="accordion-header" id="headingSolution1">
   Solution to challenge 1
   </h4>
 </button>
-<div id="collapseSolution1" class="accordion-collapse collapse" data-bs-parent="#accordionSolution1" aria-labelledby="headingSolution1">
+<div id="collapseSolution1" class="accordion-collapse collapse" aria-labelledby="headingSolution1" data-bs-parent="#accordionSolution1">
 <div class="accordion-body">
 <div class="codewrapper sourceCode" id="cb34">
 <h3 class="code-label">R<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -5645,7 +5645,7 @@ <h4 class="accordion-header" id="headingSolution2">
   Solution to challenge 2
   </h4>
 </button>
-<div id="collapseSolution2" class="accordion-collapse collapse" data-bs-parent="#accordionSolution2" aria-labelledby="headingSolution2">
+<div id="collapseSolution2" class="accordion-collapse collapse" aria-labelledby="headingSolution2" data-bs-parent="#accordionSolution2">
 <div class="accordion-body">
 <div class="codewrapper sourceCode" id="cb50">
 <h3 class="code-label">R<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -5903,7 +5903,7 @@ <h4 class="accordion-header" id="headingSolution3">
   Solution to challenge 3
   </h4>
 </button>
-<div id="collapseSolution3" class="accordion-collapse collapse" data-bs-parent="#accordionSolution3" aria-labelledby="headingSolution3">
+<div id="collapseSolution3" class="accordion-collapse collapse" aria-labelledby="headingSolution3" data-bs-parent="#accordionSolution3">
 <div class="accordion-body">
 <ul>
 <li>The <strong>wrong</strong> way to do this problem is
@@ -6199,7 +6199,7 @@ <h4 class="accordion-header" id="headingSolution4">
   Solution to challenge 4
   </h4>
 </button>
-<div id="collapseSolution4" class="accordion-collapse collapse" data-bs-parent="#accordionSolution4" aria-labelledby="headingSolution4">
+<div id="collapseSolution4" class="accordion-collapse collapse" aria-labelledby="headingSolution4" data-bs-parent="#accordionSolution4">
 <div class="accordion-body">
 <p>D</p>
 </div>
@@ -6348,7 +6348,7 @@ <h4 class="accordion-header" id="headingSolution5">
   Solution to challenge 5
   </h4>
 </button>
-<div id="collapseSolution5" class="accordion-collapse collapse" data-bs-parent="#accordionSolution5" aria-labelledby="headingSolution5">
+<div id="collapseSolution5" class="accordion-collapse collapse" aria-labelledby="headingSolution5" data-bs-parent="#accordionSolution5">
 <div class="accordion-body">
 <div class="codewrapper sourceCode" id="cb115">
 <h3 class="code-label">R<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -6414,7 +6414,7 @@ <h4 class="accordion-header" id="headingSolution6">
   Solution to challenge 6
   </h4>
 </button>
-<div id="collapseSolution6" class="accordion-collapse collapse" data-bs-parent="#accordionSolution6" aria-labelledby="headingSolution6">
+<div id="collapseSolution6" class="accordion-collapse collapse" aria-labelledby="headingSolution6" data-bs-parent="#accordionSolution6">
 <div class="accordion-body">
 <div class="codewrapper sourceCode" id="cb122">
 <h3 class="code-label">R<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -6582,7 +6582,7 @@ <h4 class="accordion-header" id="headingSolution7">
   Solution to challenge 7
   </h4>
 </button>
-<div id="collapseSolution7" class="accordion-collapse collapse" data-bs-parent="#accordionSolution7" aria-labelledby="headingSolution7">
+<div id="collapseSolution7" class="accordion-collapse collapse" aria-labelledby="headingSolution7" data-bs-parent="#accordionSolution7">
 <div class="accordion-body">
 <p>Fix each of the following common data frame subsetting errors:</p>
 <ol style="list-style-type: decimal">
@@ -6668,7 +6668,7 @@ <h4 class="accordion-header" id="headingSolution8">
   Solution to challenge 8
   </h4>
 </button>
-<div id="collapseSolution8" class="accordion-collapse collapse" data-bs-parent="#accordionSolution8" aria-labelledby="headingSolution8">
+<div id="collapseSolution8" class="accordion-collapse collapse" aria-labelledby="headingSolution8" data-bs-parent="#accordionSolution8">
 <div class="accordion-body">
 <ol style="list-style-type: decimal">
 <li><p><code>gapminder</code> is a data.frame so needs to be subsetted
@@ -6708,7 +6708,7 @@ <h3 class="callout-title">Key Points<a class="anchor" aria-label="anchor" href="
 </div>
 </section></section><section id="aio-08-plot-ggplot2"><p>Content from <a href="08-plot-ggplot2.html">Creating Publication-Quality Graphics with ggplot2</a></p>
 <hr>
-<p>Last updated on 2024-07-02 |
+<p>Last updated on 2024-08-06 |
 
         <a href="https://github.com/UCL/ClinicianCoders/edit/main/episodes/08-plot-ggplot2.Rmd" class="external-link">Edit this page <i aria-hidden="true" data-feather="edit"></i></a></p>
 <div class="text-end">
@@ -6851,7 +6851,7 @@ <h4 class="accordion-header" id="headingSolution1">
   Solution to challenge 1
   </h4>
 </button>
-<div id="collapseSolution1" class="accordion-collapse collapse" aria-labelledby="headingSolution1" data-bs-parent="#accordionSolution1">
+<div id="collapseSolution1" class="accordion-collapse collapse" data-bs-parent="#accordionSolution1" aria-labelledby="headingSolution1">
 <div class="accordion-body">
 <p>Here is one possible solution:</p>
 <div class="codewrapper sourceCode" id="cb5">
@@ -6893,7 +6893,7 @@ <h4 class="accordion-header" id="headingSolution2">
   Solution to challenge 2
   </h4>
 </button>
-<div id="collapseSolution2" class="accordion-collapse collapse" aria-labelledby="headingSolution2" data-bs-parent="#accordionSolution2">
+<div id="collapseSolution2" class="accordion-collapse collapse" data-bs-parent="#accordionSolution2" aria-labelledby="headingSolution2">
 <div class="accordion-body">
 <p>The solution presented below adds <code>color=continent</code> to the
 call of the <code>aes</code> function. The general trend seems to
@@ -7007,7 +7007,7 @@ <h4 class="accordion-header" id="headingSolution3">
   Solution to challenge 3
   </h4>
 </button>
-<div id="collapseSolution3" class="accordion-collapse collapse" aria-labelledby="headingSolution3" data-bs-parent="#accordionSolution3">
+<div id="collapseSolution3" class="accordion-collapse collapse" data-bs-parent="#accordionSolution3" aria-labelledby="headingSolution3">
 <div class="accordion-body">
 <p>The lines now get drawn over the points!</p>
 <div class="codewrapper sourceCode" id="cb11">
@@ -7141,7 +7141,7 @@ <h4 class="accordion-header" id="headingSolution4">
   Solution to challenge 4a
   </h4>
 </button>
-<div id="collapseSolution4" class="accordion-collapse collapse" aria-labelledby="headingSolution4" data-bs-parent="#accordionSolution4">
+<div id="collapseSolution4" class="accordion-collapse collapse" data-bs-parent="#accordionSolution4" aria-labelledby="headingSolution4">
 <div class="accordion-body">
 <p>Here a possible solution: Notice that the <code>color</code> argument
 is supplied outside of the <code>aes()</code> function. This means that
@@ -7186,7 +7186,7 @@ <h4 class="accordion-header" id="headingSolution5">
   Solution to challenge 4b
   </h4>
 </button>
-<div id="collapseSolution5" class="accordion-collapse collapse" aria-labelledby="headingSolution5" data-bs-parent="#accordionSolution5">
+<div id="collapseSolution5" class="accordion-collapse collapse" data-bs-parent="#accordionSolution5" aria-labelledby="headingSolution5">
 <div class="accordion-body">
 <p>Here is a possible solution: Notice that supplying the
 <code>color</code> argument inside the <code>aes()</code> functions
@@ -7349,7 +7349,7 @@ <h4 class="accordion-header" id="headingSolution6">
   Solution to Challenge 5
   </h4>
 </button>
-<div id="collapseSolution6" class="accordion-collapse collapse" aria-labelledby="headingSolution6" data-bs-parent="#accordionSolution6">
+<div id="collapseSolution6" class="accordion-collapse collapse" data-bs-parent="#accordionSolution6" aria-labelledby="headingSolution6">
 <div class="accordion-body">
 <p>Here a possible solution: <code>xlab()</code> and <code>ylab()</code>
 set labels for the x and y axes, respectively The axis title, text and
@@ -7389,7 +7389,7 @@ <h3 class="callout-title">Key Points<a class="anchor" aria-label="anchor" href="
 </div>
 </section></section><section id="aio-11-writing-data"><p>Content from <a href="11-writing-data.html">Writing Data</a></p>
 <hr>
-<p>Last updated on 2024-07-02 |
+<p>Last updated on 2024-08-06 |
 
         <a href="https://github.com/UCL/ClinicianCoders/edit/main/episodes/11-writing-data.Rmd" class="external-link">Edit this page <i aria-hidden="true" data-feather="edit"></i></a></p>
 <div class="text-end">
@@ -7641,7 +7641,7 @@ <h3 class="callout-title">Key Points<a class="anchor" aria-label="anchor" href="
 </div>
 </section></section><section id="aio-12-dplyr"><p>Content from <a href="12-dplyr.html">Data Frame Manipulation with dplyr</a></p>
 <hr>
-<p>Last updated on 2024-07-02 |
+<p>Last updated on 2024-08-06 |
 
         <a href="https://github.com/UCL/ClinicianCoders/edit/main/episodes/12-dplyr.Rmd" class="external-link">Edit this page <i aria-hidden="true" data-feather="edit"></i></a></p>
 <div class="text-end">
@@ -8462,7 +8462,7 @@ <h3 class="callout-title">Key Points<a class="anchor" aria-label="anchor" href="
 </div>
 </section></section><section id="aio-13-tidyr"><p>Content from <a href="13-tidyr.html">Data Frame Manipulation with tidyr</a></p>
 <hr>
-<p>Last updated on 2024-07-02 |
+<p>Last updated on 2024-08-06 |
 
         <a href="https://github.com/UCL/ClinicianCoders/edit/main/episodes/13-tidyr.Rmd" class="external-link">Edit this page <i aria-hidden="true" data-feather="edit"></i></a></p>
 <div class="text-end">
@@ -9197,7 +9197,7 @@ <h3 class="callout-title">Key Points<a class="anchor" aria-label="anchor" href="
 </div>
 </section></section><section id="aio-statistics"><p>Content from <a href="statistics.html">Basic Statistics: describing, modelling and reporting</a></p>
 <hr>
-<p>Last updated on 2024-07-02 |
+<p>Last updated on 2024-08-06 |
 
         <a href="https://github.com/UCL/ClinicianCoders/edit/main/episodes/statistics.Rmd" class="external-link">Edit this page <i aria-hidden="true" data-feather="edit"></i></a></p>
 <div class="text-end">
@@ -9279,12 +9279,21 @@ <h3 class="code-label">R<i aria-hidden="true" data-feather="chevron-left"></i><i
 <a class="anchor" aria-label="anchor" href="#descriptive-and-inferential-statistics"></a>
 </h2>
 <hr class="half-width">
-<div class="Background">
+<div id="callout1" class="callout">
+<div class="callout-square">
+<i class="callout-icon" data-feather="bell"></i>
+</div>
+<div class="callout-inner">
+<h3 class="callout-title">Callout<a class="anchor" aria-label="anchor" href="#callout1"></a>
+</h3>
+<div class="callout-content">
 <p>Just as data in general are of different types - for example numeric
 vs text data - statistical data are assigned to different <em>levels of
 measure</em>. The level of measure determines how we can describe and
 model the data.</p>
 </div>
+</div>
+</div>
 </section><div class="section level1">
 <h1 id="describing-data">Describing data<a class="anchor" aria-label="anchor" href="#describing-data"></a>
 </h1>
@@ -9292,12 +9301,12 @@ <h1 id="describing-data">Describing data<a class="anchor" aria-label="anchor" hr
 <li>Continuous variables</li>
 <li>Discrete variables</li>
 </ul>
-<div id="callout1" class="callout">
+<div id="callout2" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
 <div class="callout-inner">
-<h3 class="callout-title">Callout<a class="anchor" aria-label="anchor" href="#callout1"></a>
+<h3 class="callout-title">Callout<a class="anchor" aria-label="anchor" href="#callout2"></a>
 </h3>
 <div class="callout-content">
 <p>How do we convey information on what your data looks like, using
@@ -9551,8 +9560,8 @@ <h3 class="code-label">R<i aria-hidden="true" data-feather="chevron-left"></i><i
 </h3>
 <pre class="downlit sourceCode r">
 <code class="sourceCode R"><span><span class="fu">table</span><span class="op">(</span></span>
-<span>    <span class="va">gapminder</span><span class="op">$</span><span class="va">country</span><span class="op">[</span><span class="va">gapminder</span><span class="op">$</span><span class="va">year</span> <span class="op">==</span> <span class="fl">2007</span><span class="op">]</span>,</span>
-<span>    <span class="va">gapminder</span><span class="op">$</span><span class="va">continent</span><span class="op">[</span><span class="va">gapminder</span><span class="op">$</span><span class="va">year</span> <span class="op">==</span> <span class="fl">2007</span><span class="op">]</span></span>
+<span>  <span class="va">gapminder</span><span class="op">$</span><span class="va">country</span><span class="op">[</span><span class="va">gapminder</span><span class="op">$</span><span class="va">year</span> <span class="op">==</span> <span class="fl">2007</span><span class="op">]</span>,</span>
+<span>  <span class="va">gapminder</span><span class="op">$</span><span class="va">continent</span><span class="op">[</span><span class="va">gapminder</span><span class="op">$</span><span class="va">year</span> <span class="op">==</span> <span class="fl">2007</span><span class="op">]</span></span>
 <span><span class="op">)</span></span></code></pre>
 </div>
 <div class="codewrapper">
@@ -9716,12 +9725,12 @@ <h2 id="meaningful-analysis">Meaningful analysis<a class="anchor" aria-label="an
 <ul>
 <li>What is your hypothesis - what is your null hypothesis?</li>
 </ul>
-<div id="callout2" class="callout">
+<div id="callout3" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
 <div class="callout-inner">
-<h3 class="callout-title">Callout<a class="anchor" aria-label="anchor" href="#callout2"></a>
+<h3 class="callout-title">Callout<a class="anchor" aria-label="anchor" href="#callout3"></a>
 </h3>
 <div class="callout-content">
 <p>Always: the level of the independent variable has no effect on the
@@ -10104,7 +10113,7 @@ <h2 id="lunch">Lunch<a class="anchor" aria-label="anchor" href="#lunch"></a>
 </div>
 </div></section><section id="aio-14-knitr-markdown"><p>Content from <a href="14-knitr-markdown.html">Producing Reports With knitr</a></p>
 <hr>
-<p>Last updated on 2024-07-02 |
+<p>Last updated on 2024-08-06 |
 
         <a href="https://github.com/UCL/ClinicianCoders/edit/main/episodes/14-knitr-markdown.Rmd" class="external-link">Edit this page <i aria-hidden="true" data-feather="edit"></i></a></p>
 <div class="text-end">
@@ -10298,7 +10307,7 @@ <h4 class="accordion-header" id="headingSolution1">
   Solution to Challenge 1
   </h4>
 </button>
-<div id="collapseSolution1" class="accordion-collapse collapse" aria-labelledby="headingSolution1" data-bs-parent="#accordionSolution1">
+<div id="collapseSolution1" class="accordion-collapse collapse" data-bs-parent="#accordionSolution1" aria-labelledby="headingSolution1">
 <div class="accordion-body">
 <p>In RStudio, select File &gt; New file &gt; R Markdown…</p>
 <p>Delete the placeholder text and add the following:</p>
@@ -10383,7 +10392,7 @@ <h4 class="accordion-header" id="headingSolution2">
   Solution to Challenge 2
   </h4>
 </button>
-<div id="collapseSolution2" class="accordion-collapse collapse" aria-labelledby="headingSolution2" data-bs-parent="#accordionSolution2">
+<div id="collapseSolution2" class="accordion-collapse collapse" data-bs-parent="#accordionSolution2" aria-labelledby="headingSolution2">
 <div class="accordion-body">
 <pre>
 ```{r load-ggplot2}
@@ -10477,7 +10486,7 @@ <h4 class="accordion-header" id="headingSolution3">
   Solution to Challenge 3
   </h4>
 </button>
-<div id="collapseSolution3" class="accordion-collapse collapse" aria-labelledby="headingSolution3" data-bs-parent="#accordionSolution3">
+<div id="collapseSolution3" class="accordion-collapse collapse" data-bs-parent="#accordionSolution3" aria-labelledby="headingSolution3">
 <div class="accordion-body">
 <pre>
 ```{r echo = FALSE, fig.width = 3}
@@ -10529,7 +10538,7 @@ <h4 class="accordion-header" id="headingSolution4">
   Solution to Challenge 4
   </h4>
 </button>
-<div id="collapseSolution4" class="accordion-collapse collapse" aria-labelledby="headingSolution4" data-bs-parent="#accordionSolution4">
+<div id="collapseSolution4" class="accordion-collapse collapse" data-bs-parent="#accordionSolution4" aria-labelledby="headingSolution4">
 <div class="accordion-body">
 <p>Here’s some inline code to determine that 2 + 2 = <code>4</code>.</p>
 </div>
@@ -10628,7 +10637,7 @@ <h3 class="callout-title">Key Points<a class="anchor" aria-label="anchor" href="
 </div>
 </section></section><section id="aio-15-wrap-up"><p>Content from <a href="15-wrap-up.html">Writing Good Software</a></p>
 <hr>
-<p>Last updated on 2024-07-02 |
+<p>Last updated on 2024-08-06 |
 
         <a href="https://github.com/UCL/ClinicianCoders/edit/main/episodes/15-wrap-up.Rmd" class="external-link">Edit this page <i aria-hidden="true" data-feather="edit"></i></a></p>
 <div class="text-end">
diff --git a/discuss.html b/discuss.html
index eb4139b43..462c46771 100644
--- a/discuss.html
+++ b/discuss.html
@@ -368,7 +368,7 @@ <h2 class="accordion-header" id="flush-headingTwelve">
       </div>
       <hr></nav><main id="main-content" class="main-content"><div class="container lesson-content">
         <h1>Discussion</h1>
-        <p>Last updated on 2024-07-02 |
+        <p>Last updated on 2024-08-06 |
 
         <a href="https://github.com/UCL/ClinicianCoders/edit/main/learners/discuss.md" class="external-link">Edit this page <i aria-hidden="true" data-feather="edit"></i></a></p>
 
@@ -441,7 +441,7 @@ <h1>Discussion</h1>
   "url": "https://UCL.github.io/ClinicianCoders/discuss.html",
   "identifier": "https://UCL.github.io/ClinicianCoders/discuss.html",
   "dateCreated": "2023-10-26",
-  "dateModified": "2024-07-02",
+  "dateModified": "2024-08-06",
   "datePublished": "2024-08-06"
 }
 
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diff --git a/instructor/01-rstudio-intro.html b/instructor/01-rstudio-intro.html
index 343e47494..2cf6caf77 100644
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+++ b/instructor/01-rstudio-intro.html
@@ -390,7 +390,7 @@ <h2 class="accordion-header" id="flush-headingTwelve">
       </div>
       <hr></nav><main id="main-content" class="main-content"><div class="container lesson-content">
         <h1>Introduction to R and RStudio</h1>
-        <p>Last updated on 2024-07-02 |
+        <p>Last updated on 2024-08-06 |
 
         <a href="https://github.com/UCL/ClinicianCoders/edit/main/episodes/01-rstudio-intro.Rmd" class="external-link">Edit this page <i aria-hidden="true" data-feather="edit"></i></a></p>
 
@@ -1111,7 +1111,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
     }
     else all.names
 }
-&lt;bytecode: 0x561d3e951d80&gt;
+&lt;bytecode: 0x559ed2a8ed80&gt;
 &lt;environment: namespace:base&gt;</code></pre>
 </div>
 <p>What’s going on here?</p>
@@ -1489,7 +1489,7 @@ <h3 class="callout-title">Key Points<a class="anchor" aria-label="anchor" href="
   "url": "https://UCL.github.io/ClinicianCoders/instructor/01-rstudio-intro.html",
   "identifier": "https://UCL.github.io/ClinicianCoders/instructor/01-rstudio-intro.html",
   "dateCreated": "2023-10-26",
-  "dateModified": "2024-07-02",
+  "dateModified": "2024-08-06",
   "datePublished": "2024-08-06"
 }
 
diff --git a/instructor/02-project-intro.html b/instructor/02-project-intro.html
index 6208f2fb0..34f397e39 100644
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@@ -381,7 +381,7 @@ <h2 class="accordion-header" id="flush-headingTwelve">
       </div>
       <hr></nav><main id="main-content" class="main-content"><div class="container lesson-content">
         <h1>Project Management With RStudio</h1>
-        <p>Last updated on 2024-07-02 |
+        <p>Last updated on 2024-08-06 |
 
         <a href="https://github.com/UCL/ClinicianCoders/edit/main/episodes/02-project-intro.Rmd" class="external-link">Edit this page <i aria-hidden="true" data-feather="edit"></i></a></p>
 
@@ -631,7 +631,7 @@ <h3 class="code-label">SH<i aria-hidden="true" data-feather="chevron-left"></i><
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="output" tabindex="0"><code>-rw-r--r-- 1 runner docker 80K Jul  2 11:37 data/gapminder_data.csv</code></pre>
+<pre class="output" tabindex="0"><code>-rw-r--r-- 1 runner docker 80K Aug  6 12:20 data/gapminder_data.csv</code></pre>
 </div>
 <p>The file size is 80K.</p>
 <div class="codewrapper sourceCode" id="cb3">
@@ -817,7 +817,7 @@ <h3 class="callout-title">Key Points<a class="anchor" aria-label="anchor" href="
   "url": "https://UCL.github.io/ClinicianCoders/instructor/02-project-intro.html",
   "identifier": "https://UCL.github.io/ClinicianCoders/instructor/02-project-intro.html",
   "dateCreated": "2023-10-26",
-  "dateModified": "2024-07-02",
+  "dateModified": "2024-08-06",
   "datePublished": "2024-08-06"
 }
 
diff --git a/instructor/03-seeking-help.html b/instructor/03-seeking-help.html
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@@ -385,7 +385,7 @@ <h2 class="accordion-header" id="flush-headingTwelve">
       </div>
       <hr></nav><main id="main-content" class="main-content"><div class="container lesson-content">
         <h1>Seeking Help</h1>
-        <p>Last updated on 2024-07-02 |
+        <p>Last updated on 2024-08-06 |
 
         <a href="https://github.com/UCL/ClinicianCoders/edit/main/episodes/03-seeking-help.Rmd" class="external-link">Edit this page <i aria-hidden="true" data-feather="edit"></i></a></p>
 
@@ -596,8 +596,8 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 [1] stats     graphics  grDevices utils     datasets  methods   base
 
 loaded via a namespace (and not attached):
-[1] compiler_4.4.1  tools_4.4.1     yaml_2.3.8      knitr_1.47
-[5] xfun_0.45       renv_1.0.7      evaluate_0.24.0</code></pre>
+[1] compiler_4.4.1  tools_4.4.1     yaml_2.3.10     knitr_1.48
+[5] xfun_0.46       renv_1.0.7      evaluate_0.24.0</code></pre>
 </div>
 <p>Will print out your current version of R, as well as any packages you
 have loaded. This can be useful for others to help reproduce and debug
@@ -630,7 +630,7 @@ <h4 class="accordion-header" id="headingSolution1">
   Solution to Challenge 1
   </h4>
 </button>
-<div id="collapseSolution1" class="accordion-collapse collapse" data-bs-parent="#accordionSolution1" aria-labelledby="headingSolution1">
+<div id="collapseSolution1" class="accordion-collapse collapse" aria-labelledby="headingSolution1" data-bs-parent="#accordionSolution1">
 <div class="accordion-body">
 <p>The <code>c()</code> function creates a vector, in which all elements
 are of the same type. In the first case, the elements are numeric, in
@@ -661,7 +661,7 @@ <h4 class="accordion-header" id="headingSolution2">
   Solution to Challenge 2
   </h4>
 </button>
-<div id="collapseSolution2" class="accordion-collapse collapse" data-bs-parent="#accordionSolution2" aria-labelledby="headingSolution2">
+<div id="collapseSolution2" class="accordion-collapse collapse" aria-labelledby="headingSolution2" data-bs-parent="#accordionSolution2">
 <div class="accordion-body">
 <p>To look at the help for the <code>paste()</code> function, use:</p>
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   Solution to Challenge 3
   </h4>
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+<div id="collapseSolution3" class="accordion-collapse collapse" aria-labelledby="headingSolution3" data-bs-parent="#accordionSolution3">
 <div class="accordion-body">
 <p>The standard R function for reading tab-delimited files with a period
 decimal separator is read.delim(). You can also do this with
@@ -859,7 +859,7 @@ <h3 class="callout-title">Key Points<a class="anchor" aria-label="anchor" href="
   "url": "https://UCL.github.io/ClinicianCoders/instructor/03-seeking-help.html",
   "identifier": "https://UCL.github.io/ClinicianCoders/instructor/03-seeking-help.html",
   "dateCreated": "2023-10-26",
-  "dateModified": "2024-07-02",
+  "dateModified": "2024-08-06",
   "datePublished": "2024-08-06"
 }
 
diff --git a/instructor/04-data-structures-part1.html b/instructor/04-data-structures-part1.html
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       </div>
       <hr></nav><main id="main-content" class="main-content"><div class="container lesson-content">
         <h1>Data Structures</h1>
-        <p>Last updated on 2024-07-02 |
+        <p>Last updated on 2024-08-06 |
 
         <a href="https://github.com/UCL/ClinicianCoders/edit/main/episodes/04-data-structures-part1.Rmd" class="external-link">Edit this page <i aria-hidden="true" data-feather="edit"></i></a></p>
 
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   Discussion 1
   </h4>
 </button>
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 <div class="accordion-body">
 <p>By keeping everything in a column the same, we allow ourselves to
 make simple assumptions about our data; if you can interpret one entry
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   Tip 1.1
   </h4>
 </button>
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 <div class="accordion-body">
 <p>Show the content of any variable by typing its name.</p>
 <div class="section level3">
@@ -1111,7 +1111,7 @@ <h4 class="accordion-header" id="headingSolution3">
   Tip 1.2
   </h4>
 </button>
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 <p>In the chapter “Data types” we saw two functions that can show data
 types. One printed just a single word, the data type name. The other
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   Tip 1.3
   </h4>
 </button>
-<div id="collapseSolution4" class="accordion-collapse collapse" aria-labelledby="headingSolution4" data-bs-parent="#accordionSolution4">
+<div id="collapseSolution4" class="accordion-collapse collapse" data-bs-parent="#accordionSolution4" aria-labelledby="headingSolution4">
 <div class="accordion-body">
 <p>Scroll up to the section about the <a href="#the-type-hierarchy">type
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   Solution to Challenge 1.3
   </h4>
 </button>
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 <div class="accordion-body">
 <ul><li>Weight is expressed on a continuous scale (real numbers). The R data
 type for this is “double” (also known as “numeric”).</li>
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   Tip 1.4
   </h4>
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 <p>Revisit the hierarchy of data types when two different data types are
 combined.</p>
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   Tip 1.5
   </h4>
 </button>
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 <div class="accordion-body">
 <p>The functions to convert data types start with <code>as.</code>. You
 can look for the function further up in the manuscript or use the
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   Solution to Challenge 2
   </h4>
 </button>
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   Solution to Challenge 3
   </h4>
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-<div id="collapseSolution9" class="accordion-collapse collapse" aria-labelledby="headingSolution9" data-bs-parent="#accordionSolution9">
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 <p>You get the names of an object by wrapping the object name inside
 <code>names(...)</code>. Similarly, you get the data type of the names
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   Solution to Challenge 4
   </h4>
 </button>
-<div id="collapseSolution10" class="accordion-collapse collapse" aria-labelledby="headingSolution10" data-bs-parent="#accordionSolution10">
+<div id="collapseSolution10" class="accordion-collapse collapse" data-bs-parent="#accordionSolution10" aria-labelledby="headingSolution10">
 <div class="accordion-body">
 <pre><code><span><span class="va">letter_no</span> <span class="op">&lt;-</span> <span class="fl">1</span><span class="op">:</span><span class="fl">26</span>   <span class="co"># or seq(1,26)</span></span>
 <span><span class="fu">names</span><span class="op">(</span><span class="va">letter_no</span><span class="op">)</span> <span class="op">&lt;-</span> <span class="va">LETTERS</span></span>
@@ -1894,7 +1894,7 @@ <h4 class="accordion-header" id="headingSolution11">
   Solution to Challenge 5
   </h4>
 </button>
-<div id="collapseSolution11" class="accordion-collapse collapse" aria-labelledby="headingSolution11" data-bs-parent="#accordionSolution11">
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 <div class="accordion-body">
 <div class="codewrapper sourceCode" id="cb138">
 <h3 class="code-label">R<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -2156,7 +2156,7 @@ <h4 class="accordion-header" id="headingSolution12">
   Solution to Challenge 6
   </h4>
 </button>
-<div id="collapseSolution12" class="accordion-collapse collapse" aria-labelledby="headingSolution12" data-bs-parent="#accordionSolution12">
+<div id="collapseSolution12" class="accordion-collapse collapse" data-bs-parent="#accordionSolution12" aria-labelledby="headingSolution12">
 <div class="accordion-body">
 <p>What do you think will be the result of
 <code>length(matrix_example)</code>?</p>
@@ -2202,7 +2202,7 @@ <h4 class="accordion-header" id="headingSolution13">
   Solution to Challenge 7
   </h4>
 </button>
-<div id="collapseSolution13" class="accordion-collapse collapse" aria-labelledby="headingSolution13" data-bs-parent="#accordionSolution13">
+<div id="collapseSolution13" class="accordion-collapse collapse" data-bs-parent="#accordionSolution13" aria-labelledby="headingSolution13">
 <div class="accordion-body">
 <p>Make another matrix, this time containing the numbers 1:50, with 5
 columns and 10 rows. Did the <code>matrix</code> function fill your
@@ -2244,7 +2244,7 @@ <h4 class="accordion-header" id="headingSolution14">
   Solution to Challenge 8
   </h4>
 </button>
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   Solution to Challenge 9
   </h4>
 </button>
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+<div id="collapseSolution15" class="accordion-collapse collapse" data-bs-parent="#accordionSolution15" aria-labelledby="headingSolution15">
 <div class="accordion-body">
 <p>Consider the R output of the matrix below:</p>
 <div class="codewrapper">
@@ -2395,7 +2395,7 @@ <h3 class="callout-title">Key Points<a class="anchor" aria-label="anchor" href="
   "url": "https://UCL.github.io/ClinicianCoders/instructor/04-data-structures-part1.html",
   "identifier": "https://UCL.github.io/ClinicianCoders/instructor/04-data-structures-part1.html",
   "dateCreated": "2023-10-26",
-  "dateModified": "2024-07-02",
+  "dateModified": "2024-08-06",
   "datePublished": "2024-08-06"
 }
 
diff --git a/instructor/05-data-structures-part2.html b/instructor/05-data-structures-part2.html
index cf30ece1d..b26fea940 100644
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+++ b/instructor/05-data-structures-part2.html
@@ -383,7 +383,7 @@ <h2 class="accordion-header" id="flush-headingTwelve">
       </div>
       <hr></nav><main id="main-content" class="main-content"><div class="container lesson-content">
         <h1>Exploring Data Frames</h1>
-        <p>Last updated on 2024-07-02 |
+        <p>Last updated on 2024-08-06 |
 
         <a href="https://github.com/UCL/ClinicianCoders/edit/main/episodes/05-data-structures-part2.Rmd" class="external-link">Edit this page <i aria-hidden="true" data-feather="edit"></i></a></p>
 
@@ -1186,7 +1186,7 @@ <h3 class="callout-title">Key Points<a class="anchor" aria-label="anchor" href="
   "url": "https://UCL.github.io/ClinicianCoders/instructor/05-data-structures-part2.html",
   "identifier": "https://UCL.github.io/ClinicianCoders/instructor/05-data-structures-part2.html",
   "dateCreated": "2023-10-26",
-  "dateModified": "2024-07-02",
+  "dateModified": "2024-08-06",
   "datePublished": "2024-08-06"
 }
 
diff --git a/instructor/06-data-subsetting.html b/instructor/06-data-subsetting.html
index 01ac23b12..371a0d876 100644
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       </div>
       <hr></nav><main id="main-content" class="main-content"><div class="container lesson-content">
         <h1>Subsetting Data</h1>
-        <p>Last updated on 2024-07-02 |
+        <p>Last updated on 2024-08-06 |
 
         <a href="https://github.com/UCL/ClinicianCoders/edit/main/episodes/06-data-subsetting.Rmd" class="external-link">Edit this page <i aria-hidden="true" data-feather="edit"></i></a></p>
 
@@ -728,7 +728,7 @@ <h4 class="accordion-header" id="headingSolution1">
   Solution to challenge 1
   </h4>
 </button>
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   Solution to challenge 2
   </h4>
 </button>
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   Solution to challenge 3
   </h4>
 </button>
-<div id="collapseSolution3" class="accordion-collapse collapse" data-bs-parent="#accordionSolution3" aria-labelledby="headingSolution3">
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 <div class="accordion-body">
 <ul><li>The <strong>wrong</strong> way to do this problem is
 <code>countries==seAsia</code>. This gives a warning
@@ -1455,7 +1455,7 @@ <h4 class="accordion-header" id="headingSolution4">
   Solution to challenge 4
   </h4>
 </button>
-<div id="collapseSolution4" class="accordion-collapse collapse" data-bs-parent="#accordionSolution4" aria-labelledby="headingSolution4">
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 <p>D</p>
 </div>
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   Solution to challenge 5
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 </button>
-<div id="collapseSolution5" class="accordion-collapse collapse" data-bs-parent="#accordionSolution5" aria-labelledby="headingSolution5">
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 <div class="accordion-body">
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@@ -1668,7 +1668,7 @@ <h4 class="accordion-header" id="headingSolution6">
   Solution to challenge 6
   </h4>
 </button>
-<div id="collapseSolution6" class="accordion-collapse collapse" data-bs-parent="#accordionSolution6" aria-labelledby="headingSolution6">
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 <div class="accordion-body">
 <div class="codewrapper sourceCode" id="cb122">
 <h3 class="code-label">R<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -1824,7 +1824,7 @@ <h4 class="accordion-header" id="headingSolution7">
   Solution to challenge 7
   </h4>
 </button>
-<div id="collapseSolution7" class="accordion-collapse collapse" data-bs-parent="#accordionSolution7" aria-labelledby="headingSolution7">
+<div id="collapseSolution7" class="accordion-collapse collapse" aria-labelledby="headingSolution7" data-bs-parent="#accordionSolution7">
 <div class="accordion-body">
 <p>Fix each of the following common data frame subsetting errors:</p>
 <ol style="list-style-type: decimal"><li>Extract observations collected for the year 1957</li>
@@ -1898,7 +1898,7 @@ <h4 class="accordion-header" id="headingSolution8">
   Solution to challenge 8
   </h4>
 </button>
-<div id="collapseSolution8" class="accordion-collapse collapse" data-bs-parent="#accordionSolution8" aria-labelledby="headingSolution8">
+<div id="collapseSolution8" class="accordion-collapse collapse" aria-labelledby="headingSolution8" data-bs-parent="#accordionSolution8">
 <div class="accordion-body">
 <ol style="list-style-type: decimal"><li><p><code>gapminder</code> is a data.frame so needs to be subsetted
 on two dimensions. <code>gapminder[1:20, ]</code> subsets the data to
@@ -1990,7 +1990,7 @@ <h3 class="callout-title">Key Points<a class="anchor" aria-label="anchor" href="
   "url": "https://UCL.github.io/ClinicianCoders/instructor/06-data-subsetting.html",
   "identifier": "https://UCL.github.io/ClinicianCoders/instructor/06-data-subsetting.html",
   "dateCreated": "2023-10-26",
-  "dateModified": "2024-07-02",
+  "dateModified": "2024-08-06",
   "datePublished": "2024-08-06"
 }
 
diff --git a/instructor/08-plot-ggplot2.html b/instructor/08-plot-ggplot2.html
index 76d6febf9..3d0674d5f 100644
--- a/instructor/08-plot-ggplot2.html
+++ b/instructor/08-plot-ggplot2.html
@@ -383,7 +383,7 @@ <h2 class="accordion-header" id="flush-headingTwelve">
       </div>
       <hr></nav><main id="main-content" class="main-content"><div class="container lesson-content">
         <h1>Creating Publication-Quality Graphics with ggplot2</h1>
-        <p>Last updated on 2024-07-02 |
+        <p>Last updated on 2024-08-06 |
 
         <a href="https://github.com/UCL/ClinicianCoders/edit/main/episodes/08-plot-ggplot2.Rmd" class="external-link">Edit this page <i aria-hidden="true" data-feather="edit"></i></a></p>
 
@@ -528,7 +528,7 @@ <h4 class="accordion-header" id="headingSolution1">
   Solution to challenge 1
   </h4>
 </button>
-<div id="collapseSolution1" class="accordion-collapse collapse" aria-labelledby="headingSolution1" data-bs-parent="#accordionSolution1">
+<div id="collapseSolution1" class="accordion-collapse collapse" data-bs-parent="#accordionSolution1" aria-labelledby="headingSolution1">
 <div class="accordion-body">
 <p>Here is one possible solution:</p>
 <div class="codewrapper sourceCode" id="cb5">
@@ -569,7 +569,7 @@ <h4 class="accordion-header" id="headingSolution2">
   Solution to challenge 2
   </h4>
 </button>
-<div id="collapseSolution2" class="accordion-collapse collapse" aria-labelledby="headingSolution2" data-bs-parent="#accordionSolution2">
+<div id="collapseSolution2" class="accordion-collapse collapse" data-bs-parent="#accordionSolution2" aria-labelledby="headingSolution2">
 <div class="accordion-body">
 <p>The solution presented below adds <code>color=continent</code> to the
 call of the <code>aes</code> function. The general trend seems to
@@ -680,7 +680,7 @@ <h4 class="accordion-header" id="headingSolution3">
   Solution to challenge 3
   </h4>
 </button>
-<div id="collapseSolution3" class="accordion-collapse collapse" aria-labelledby="headingSolution3" data-bs-parent="#accordionSolution3">
+<div id="collapseSolution3" class="accordion-collapse collapse" data-bs-parent="#accordionSolution3" aria-labelledby="headingSolution3">
 <div class="accordion-body">
 <p>The lines now get drawn over the points!</p>
 <div class="codewrapper sourceCode" id="cb11">
@@ -811,7 +811,7 @@ <h4 class="accordion-header" id="headingSolution4">
   Solution to challenge 4a
   </h4>
 </button>
-<div id="collapseSolution4" class="accordion-collapse collapse" aria-labelledby="headingSolution4" data-bs-parent="#accordionSolution4">
+<div id="collapseSolution4" class="accordion-collapse collapse" data-bs-parent="#accordionSolution4" aria-labelledby="headingSolution4">
 <div class="accordion-body">
 <p>Here a possible solution: Notice that the <code>color</code> argument
 is supplied outside of the <code>aes()</code> function. This means that
@@ -855,7 +855,7 @@ <h4 class="accordion-header" id="headingSolution5">
   Solution to challenge 4b
   </h4>
 </button>
-<div id="collapseSolution5" class="accordion-collapse collapse" aria-labelledby="headingSolution5" data-bs-parent="#accordionSolution5">
+<div id="collapseSolution5" class="accordion-collapse collapse" data-bs-parent="#accordionSolution5" aria-labelledby="headingSolution5">
 <div class="accordion-body">
 <p>Here is a possible solution: Notice that supplying the
 <code>color</code> argument inside the <code>aes()</code> functions
@@ -1009,7 +1009,7 @@ <h4 class="accordion-header" id="headingSolution6">
   Solution to Challenge 5
   </h4>
 </button>
-<div id="collapseSolution6" class="accordion-collapse collapse" aria-labelledby="headingSolution6" data-bs-parent="#accordionSolution6">
+<div id="collapseSolution6" class="accordion-collapse collapse" data-bs-parent="#accordionSolution6" aria-labelledby="headingSolution6">
 <div class="accordion-body">
 <p>Here a possible solution: <code>xlab()</code> and <code>ylab()</code>
 set labels for the x and y axes, respectively The axis title, text and
@@ -1102,7 +1102,7 @@ <h3 class="callout-title">Key Points<a class="anchor" aria-label="anchor" href="
   "url": "https://UCL.github.io/ClinicianCoders/instructor/08-plot-ggplot2.html",
   "identifier": "https://UCL.github.io/ClinicianCoders/instructor/08-plot-ggplot2.html",
   "dateCreated": "2023-10-26",
-  "dateModified": "2024-07-02",
+  "dateModified": "2024-08-06",
   "datePublished": "2024-08-06"
 }
 
diff --git a/instructor/11-writing-data.html b/instructor/11-writing-data.html
index bcedf28e2..cd9b12c56 100644
--- a/instructor/11-writing-data.html
+++ b/instructor/11-writing-data.html
@@ -380,7 +380,7 @@ <h2 class="accordion-header" id="flush-headingTwelve">
       </div>
       <hr></nav><main id="main-content" class="main-content"><div class="container lesson-content">
         <h1>Writing Data</h1>
-        <p>Last updated on 2024-07-02 |
+        <p>Last updated on 2024-08-06 |
 
         <a href="https://github.com/UCL/ClinicianCoders/edit/main/episodes/11-writing-data.Rmd" class="external-link">Edit this page <i aria-hidden="true" data-feather="edit"></i></a></p>
 
@@ -686,7 +686,7 @@ <h3 class="callout-title">Key Points<a class="anchor" aria-label="anchor" href="
   "url": "https://UCL.github.io/ClinicianCoders/instructor/11-writing-data.html",
   "identifier": "https://UCL.github.io/ClinicianCoders/instructor/11-writing-data.html",
   "dateCreated": "2023-10-26",
-  "dateModified": "2024-07-02",
+  "dateModified": "2024-08-06",
   "datePublished": "2024-08-06"
 }
 
diff --git a/instructor/12-dplyr.html b/instructor/12-dplyr.html
index 005fb60dd..e2135186a 100644
--- a/instructor/12-dplyr.html
+++ b/instructor/12-dplyr.html
@@ -388,7 +388,7 @@ <h2 class="accordion-header" id="flush-headingTwelve">
       </div>
       <hr></nav><main id="main-content" class="main-content"><div class="container lesson-content">
         <h1>Data Frame Manipulation with dplyr</h1>
-        <p>Last updated on 2024-07-02 |
+        <p>Last updated on 2024-08-06 |
 
         <a href="https://github.com/UCL/ClinicianCoders/edit/main/episodes/12-dplyr.Rmd" class="external-link">Edit this page <i aria-hidden="true" data-feather="edit"></i></a></p>
 
@@ -1243,7 +1243,7 @@ <h3 class="callout-title">Key Points<a class="anchor" aria-label="anchor" href="
   "url": "https://UCL.github.io/ClinicianCoders/instructor/12-dplyr.html",
   "identifier": "https://UCL.github.io/ClinicianCoders/instructor/12-dplyr.html",
   "dateCreated": "2023-10-26",
-  "dateModified": "2024-07-02",
+  "dateModified": "2024-08-06",
   "datePublished": "2024-08-06"
 }
 
diff --git a/instructor/13-tidyr.html b/instructor/13-tidyr.html
index 887d84566..ca944536f 100644
--- a/instructor/13-tidyr.html
+++ b/instructor/13-tidyr.html
@@ -382,7 +382,7 @@ <h2 class="accordion-header" id="flush-headingTwelve">
       </div>
       <hr></nav><main id="main-content" class="main-content"><div class="container lesson-content">
         <h1>Data Frame Manipulation with tidyr</h1>
-        <p>Last updated on 2024-07-02 |
+        <p>Last updated on 2024-08-06 |
 
         <a href="https://github.com/UCL/ClinicianCoders/edit/main/episodes/13-tidyr.Rmd" class="external-link">Edit this page <i aria-hidden="true" data-feather="edit"></i></a></p>
 
@@ -1163,7 +1163,7 @@ <h3 class="callout-title">Key Points<a class="anchor" aria-label="anchor" href="
   "url": "https://UCL.github.io/ClinicianCoders/instructor/13-tidyr.html",
   "identifier": "https://UCL.github.io/ClinicianCoders/instructor/13-tidyr.html",
   "dateCreated": "2023-10-26",
-  "dateModified": "2024-07-02",
+  "dateModified": "2024-08-06",
   "datePublished": "2024-08-06"
 }
 
diff --git a/instructor/14-knitr-markdown.html b/instructor/14-knitr-markdown.html
index 1d2996e77..18413bab0 100644
--- a/instructor/14-knitr-markdown.html
+++ b/instructor/14-knitr-markdown.html
@@ -390,7 +390,7 @@ <h2 class="accordion-header" id="flush-headingTwelve">
       </div>
       <hr></nav><main id="main-content" class="main-content"><div class="container lesson-content">
         <h1>Producing Reports With knitr</h1>
-        <p>Last updated on 2024-07-02 |
+        <p>Last updated on 2024-08-06 |
 
         <a href="https://github.com/UCL/ClinicianCoders/edit/main/episodes/14-knitr-markdown.Rmd" class="external-link">Edit this page <i aria-hidden="true" data-feather="edit"></i></a></p>
 
@@ -574,7 +574,7 @@ <h4 class="accordion-header" id="headingSolution1">
   Solution to Challenge 1
   </h4>
 </button>
-<div id="collapseSolution1" class="accordion-collapse collapse" aria-labelledby="headingSolution1" data-bs-parent="#accordionSolution1">
+<div id="collapseSolution1" class="accordion-collapse collapse" data-bs-parent="#accordionSolution1" aria-labelledby="headingSolution1">
 <div class="accordion-body">
 <p>In RStudio, select File &gt; New file &gt; R Markdown…</p>
 <p>Delete the placeholder text and add the following:</p>
@@ -653,7 +653,7 @@ <h4 class="accordion-header" id="headingSolution2">
   Solution to Challenge 2
   </h4>
 </button>
-<div id="collapseSolution2" class="accordion-collapse collapse" aria-labelledby="headingSolution2" data-bs-parent="#accordionSolution2">
+<div id="collapseSolution2" class="accordion-collapse collapse" data-bs-parent="#accordionSolution2" aria-labelledby="headingSolution2">
 <div class="accordion-body">
 <pre>
 ```{r load-ggplot2}
@@ -741,7 +741,7 @@ <h4 class="accordion-header" id="headingSolution3">
   Solution to Challenge 3
   </h4>
 </button>
-<div id="collapseSolution3" class="accordion-collapse collapse" aria-labelledby="headingSolution3" data-bs-parent="#accordionSolution3">
+<div id="collapseSolution3" class="accordion-collapse collapse" data-bs-parent="#accordionSolution3" aria-labelledby="headingSolution3">
 <div class="accordion-body">
 <pre>
 ```{r echo = FALSE, fig.width = 3}
@@ -791,7 +791,7 @@ <h4 class="accordion-header" id="headingSolution4">
   Solution to Challenge 4
   </h4>
 </button>
-<div id="collapseSolution4" class="accordion-collapse collapse" aria-labelledby="headingSolution4" data-bs-parent="#accordionSolution4">
+<div id="collapseSolution4" class="accordion-collapse collapse" data-bs-parent="#accordionSolution4" aria-labelledby="headingSolution4">
 <div class="accordion-body">
 <p>Here’s some inline code to determine that 2 + 2 = <code>4</code>.</p>
 </div>
@@ -938,7 +938,7 @@ <h3 class="callout-title">Key Points<a class="anchor" aria-label="anchor" href="
   "url": "https://UCL.github.io/ClinicianCoders/instructor/14-knitr-markdown.html",
   "identifier": "https://UCL.github.io/ClinicianCoders/instructor/14-knitr-markdown.html",
   "dateCreated": "2023-10-26",
-  "dateModified": "2024-07-02",
+  "dateModified": "2024-08-06",
   "datePublished": "2024-08-06"
 }
 
diff --git a/instructor/15-wrap-up.html b/instructor/15-wrap-up.html
index 450b6af12..a6d8b0378 100644
--- a/instructor/15-wrap-up.html
+++ b/instructor/15-wrap-up.html
@@ -386,7 +386,7 @@ <h2 class="accordion-header" id="flush-headingTwelve">
       </div>
       <hr></nav><main id="main-content" class="main-content"><div class="container lesson-content">
         <h1>Writing Good Software</h1>
-        <p>Last updated on 2024-07-02 |
+        <p>Last updated on 2024-08-06 |
 
         <a href="https://github.com/UCL/ClinicianCoders/edit/main/episodes/15-wrap-up.Rmd" class="external-link">Edit this page <i aria-hidden="true" data-feather="edit"></i></a></p>
 
@@ -585,7 +585,7 @@ <h3 class="callout-title">Key Points<a class="anchor" aria-label="anchor" href="
   "url": "https://UCL.github.io/ClinicianCoders/instructor/15-wrap-up.html",
   "identifier": "https://UCL.github.io/ClinicianCoders/instructor/15-wrap-up.html",
   "dateCreated": "2023-10-26",
-  "dateModified": "2024-07-02",
+  "dateModified": "2024-08-06",
   "datePublished": "2024-08-06"
 }
 
diff --git a/instructor/CODE_OF_CONDUCT.html b/instructor/CODE_OF_CONDUCT.html
index 8ec634ade..bfb7fd9f4 100644
--- a/instructor/CODE_OF_CONDUCT.html
+++ b/instructor/CODE_OF_CONDUCT.html
@@ -368,7 +368,7 @@ <h2 class="accordion-header" id="flush-headingTwelve">
       </div>
       <hr></nav><main id="main-content" class="main-content"><div class="container lesson-content">
         <h1>Contributor Code of Conduct</h1>
-        <p>Last updated on 2024-07-02 |
+        <p>Last updated on 2024-08-06 |
 
         <a href="https://github.com/UCL/ClinicianCoders/edit/main/CODE_OF_CONDUCT.md" class="external-link">Edit this page <i aria-hidden="true" data-feather="edit"></i></a></p>
 
@@ -449,7 +449,7 @@ <h1>Contributor Code of Conduct</h1>
   "url": "https://UCL.github.io/ClinicianCoders/instructor/CODE_OF_CONDUCT.html",
   "identifier": "https://UCL.github.io/ClinicianCoders/instructor/CODE_OF_CONDUCT.html",
   "dateCreated": "2023-10-26",
-  "dateModified": "2024-07-02",
+  "dateModified": "2024-08-06",
   "datePublished": "2024-08-06"
 }
 
diff --git a/instructor/LICENSE.html b/instructor/LICENSE.html
index f62014499..0a2e0168e 100644
--- a/instructor/LICENSE.html
+++ b/instructor/LICENSE.html
@@ -368,7 +368,7 @@ <h2 class="accordion-header" id="flush-headingTwelve">
       </div>
       <hr></nav><main id="main-content" class="main-content"><div class="container lesson-content">
         <h1>Licenses</h1>
-        <p>Last updated on 2024-07-02 |
+        <p>Last updated on 2024-08-06 |
 
         <a href="https://github.com/UCL/ClinicianCoders/edit/main/LICENSE.md" class="external-link">Edit this page <i aria-hidden="true" data-feather="edit"></i></a></p>
 
@@ -500,7 +500,7 @@ <h1>Licenses</h1>
   "url": "https://UCL.github.io/ClinicianCoders/instructor/LICENSE.html",
   "identifier": "https://UCL.github.io/ClinicianCoders/instructor/LICENSE.html",
   "dateCreated": "2023-10-26",
-  "dateModified": "2024-07-02",
+  "dateModified": "2024-08-06",
   "datePublished": "2024-08-06"
 }
 
diff --git a/instructor/aio.html b/instructor/aio.html
index a9602f7ec..e0ff3488e 100644
--- a/instructor/aio.html
+++ b/instructor/aio.html
@@ -447,7 +447,7 @@ <h2 class="accordion-header" id="flush-headingTwelve">
         
 <section id="aio-01-rstudio-intro"><p>Content from <a href="01-rstudio-intro.html">Introduction to R and RStudio</a></p>
 <hr>
-<p>Last updated on 2024-07-02 |
+<p>Last updated on 2024-08-06 |
 
         <a href="https://github.com/UCL/ClinicianCoders/edit/main/episodes/01-rstudio-intro.Rmd" class="external-link">Edit this page <i aria-hidden="true" data-feather="edit"></i></a></p>
 <p>Estimated time: <i aria-hidden="true" data-feather="clock"></i> 55 minutes</p>
@@ -1204,7 +1204,7 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
     }
     else all.names
 }
-&lt;bytecode: 0x561d3e951d80&gt;
+&lt;bytecode: 0x559ed2a8ed80&gt;
 &lt;environment: namespace:base&gt;</code></pre>
 </div>
 <p>What’s going on here?</p>
@@ -1532,7 +1532,7 @@ <h3 class="callout-title">Key Points<a class="anchor" aria-label="anchor" href="
 </div>
 </section></section><section id="aio-02-project-intro"><p>Content from <a href="02-project-intro.html">Project Management With RStudio</a></p>
 <hr>
-<p>Last updated on 2024-07-02 |
+<p>Last updated on 2024-08-06 |
 
         <a href="https://github.com/UCL/ClinicianCoders/edit/main/episodes/02-project-intro.Rmd" class="external-link">Edit this page <i aria-hidden="true" data-feather="edit"></i></a></p>
 <p>Estimated time: <i aria-hidden="true" data-feather="clock"></i> 30 minutes</p>
@@ -1803,7 +1803,7 @@ <h3 class="code-label">SH<i aria-hidden="true" data-feather="chevron-left"></i><
 <div class="codewrapper">
 <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
 </h3>
-<pre class="output" tabindex="0"><code>-rw-r--r-- 1 runner docker 80K Jul  2 11:37 data/gapminder_data.csv</code></pre>
+<pre class="output" tabindex="0"><code>-rw-r--r-- 1 runner docker 80K Aug  6 12:20 data/gapminder_data.csv</code></pre>
 </div>
 <p>The file size is 80K.</p>
 <div class="codewrapper sourceCode" id="cb3">
@@ -1941,7 +1941,7 @@ <h3 class="callout-title">Key Points<a class="anchor" aria-label="anchor" href="
 </div>
 </section></section><section id="aio-03-seeking-help"><p>Content from <a href="03-seeking-help.html">Seeking Help</a></p>
 <hr>
-<p>Last updated on 2024-07-02 |
+<p>Last updated on 2024-08-06 |
 
         <a href="https://github.com/UCL/ClinicianCoders/edit/main/episodes/03-seeking-help.Rmd" class="external-link">Edit this page <i aria-hidden="true" data-feather="edit"></i></a></p>
 <p>Estimated time: <i aria-hidden="true" data-feather="clock"></i> 20 minutes</p>
@@ -2163,8 +2163,8 @@ <h3 class="code-label">OUTPUT<i aria-hidden="true" data-feather="chevron-left"><
 [1] stats     graphics  grDevices utils     datasets  methods   base
 
 loaded via a namespace (and not attached):
-[1] compiler_4.4.1  tools_4.4.1     yaml_2.3.8      knitr_1.47
-[5] xfun_0.45       renv_1.0.7      evaluate_0.24.0</code></pre>
+[1] compiler_4.4.1  tools_4.4.1     yaml_2.3.10     knitr_1.48
+[5] xfun_0.46       renv_1.0.7      evaluate_0.24.0</code></pre>
 </div>
 <p>Will print out your current version of R, as well as any packages you
 have loaded. This can be useful for others to help reproduce and debug
@@ -2197,7 +2197,7 @@ <h4 class="accordion-header" id="headingSolution1">
   Solution to Challenge 1
   </h4>
 </button>
-<div id="collapseSolution1" class="accordion-collapse collapse" data-bs-parent="#accordionSolution1" aria-labelledby="headingSolution1">
+<div id="collapseSolution1" class="accordion-collapse collapse" aria-labelledby="headingSolution1" data-bs-parent="#accordionSolution1">
 <div class="accordion-body">
 <p>The <code>c()</code> function creates a vector, in which all elements
 are of the same type. In the first case, the elements are numeric, in
@@ -2228,7 +2228,7 @@ <h4 class="accordion-header" id="headingSolution2">
   Solution to Challenge 2
   </h4>
 </button>
-<div id="collapseSolution2" class="accordion-collapse collapse" data-bs-parent="#accordionSolution2" aria-labelledby="headingSolution2">
+<div id="collapseSolution2" class="accordion-collapse collapse" aria-labelledby="headingSolution2" data-bs-parent="#accordionSolution2">
 <div class="accordion-body">
 <p>To look at the help for the <code>paste()</code> function, use:</p>
 <div class="codewrapper sourceCode" id="cb11">
@@ -2338,7 +2338,7 @@ <h4 class="accordion-header" id="headingSolution3">
   Solution to Challenge 3
   </h4>
 </button>
-<div id="collapseSolution3" class="accordion-collapse collapse" data-bs-parent="#accordionSolution3" aria-labelledby="headingSolution3">
+<div id="collapseSolution3" class="accordion-collapse collapse" aria-labelledby="headingSolution3" data-bs-parent="#accordionSolution3">
 <div class="accordion-body">
 <p>The standard R function for reading tab-delimited files with a period
 decimal separator is read.delim(). You can also do this with
@@ -2376,7 +2376,7 @@ <h3 class="callout-title">Key Points<a class="anchor" aria-label="anchor" href="
 </div>
 </section></section><section id="aio-04-data-structures-part1"><p>Content from <a href="04-data-structures-part1.html">Data Structures</a></p>
 <hr>
-<p>Last updated on 2024-07-02 |
+<p>Last updated on 2024-08-06 |
 
         <a href="https://github.com/UCL/ClinicianCoders/edit/main/episodes/04-data-structures-part1.Rmd" class="external-link">Edit this page <i aria-hidden="true" data-feather="edit"></i></a></p>
 <p>Estimated time: <i aria-hidden="true" data-feather="clock"></i> 55 minutes</p>
@@ -2847,7 +2847,7 @@ <h4 class="accordion-header" id="headingSolution1">
   Discussion 1
   </h4>
 </button>
-<div id="collapseSolution1" class="accordion-collapse collapse" aria-labelledby="headingSolution1" data-bs-parent="#accordionSolution1">
+<div id="collapseSolution1" class="accordion-collapse collapse" data-bs-parent="#accordionSolution1" aria-labelledby="headingSolution1">
 <div class="accordion-body">
 <p>By keeping everything in a column the same, we allow ourselves to
 make simple assumptions about our data; if you can interpret one entry
@@ -3079,7 +3079,7 @@ <h4 class="accordion-header" id="headingSolution2">
   Tip 1.1
   </h4>
 </button>
-<div id="collapseSolution2" class="accordion-collapse collapse" aria-labelledby="headingSolution2" data-bs-parent="#accordionSolution2">
+<div id="collapseSolution2" class="accordion-collapse collapse" data-bs-parent="#accordionSolution2" aria-labelledby="headingSolution2">
 <div class="accordion-body">
 <p>Show the content of any variable by typing its name.</p>
 <div class="section level3">
@@ -3114,7 +3114,7 @@ <h4 class="accordion-header" id="headingSolution3">
   Tip 1.2
   </h4>
 </button>
-<div id="collapseSolution3" class="accordion-collapse collapse" aria-labelledby="headingSolution3" data-bs-parent="#accordionSolution3">
+<div id="collapseSolution3" class="accordion-collapse collapse" data-bs-parent="#accordionSolution3" aria-labelledby="headingSolution3">
 <div class="accordion-body">
 <p>In the chapter “Data types” we saw two functions that can show data
 types. One printed just a single word, the data type name. The other
@@ -3158,7 +3158,7 @@ <h4 class="accordion-header" id="headingSolution4">
   Tip 1.3
   </h4>
 </button>
-<div id="collapseSolution4" class="accordion-collapse collapse" aria-labelledby="headingSolution4" data-bs-parent="#accordionSolution4">
+<div id="collapseSolution4" class="accordion-collapse collapse" data-bs-parent="#accordionSolution4" aria-labelledby="headingSolution4">
 <div class="accordion-body">
 <p>Scroll up to the section about the <a href="#the-type-hierarchy">type
 hierarchy</a> to review the available data types</p>
@@ -3173,7 +3173,7 @@ <h4 class="accordion-header" id="headingSolution5">
   Solution to Challenge 1.3
   </h4>
 </button>
-<div id="collapseSolution5" class="accordion-collapse collapse" aria-labelledby="headingSolution5" data-bs-parent="#accordionSolution5">
+<div id="collapseSolution5" class="accordion-collapse collapse" data-bs-parent="#accordionSolution5" aria-labelledby="headingSolution5">
 <div class="accordion-body">
 <ul>
 <li>Weight is expressed on a continuous scale (real numbers). The R data
@@ -3209,7 +3209,7 @@ <h4 class="accordion-header" id="headingSolution6">
   Tip 1.4
   </h4>
 </button>
-<div id="collapseSolution6" class="accordion-collapse collapse" aria-labelledby="headingSolution6" data-bs-parent="#accordionSolution6">
+<div id="collapseSolution6" class="accordion-collapse collapse" data-bs-parent="#accordionSolution6" aria-labelledby="headingSolution6">
 <div class="accordion-body">
 <p>Revisit the hierarchy of data types when two different data types are
 combined.</p>
@@ -3250,7 +3250,7 @@ <h4 class="accordion-header" id="headingSolution7">
   Tip 1.5
   </h4>
 </button>
-<div id="collapseSolution7" class="accordion-collapse collapse" aria-labelledby="headingSolution7" data-bs-parent="#accordionSolution7">
+<div id="collapseSolution7" class="accordion-collapse collapse" data-bs-parent="#accordionSolution7" aria-labelledby="headingSolution7">
 <div class="accordion-body">
 <p>The functions to convert data types start with <code>as.</code>. You
 can look for the function further up in the manuscript or use the
@@ -3443,7 +3443,7 @@ <h4 class="accordion-header" id="headingSolution8">
   Solution to Challenge 2
   </h4>
 </button>
-<div id="collapseSolution8" class="accordion-collapse collapse" aria-labelledby="headingSolution8" data-bs-parent="#accordionSolution8">
+<div id="collapseSolution8" class="accordion-collapse collapse" data-bs-parent="#accordionSolution8" aria-labelledby="headingSolution8">
 <div class="accordion-body">
 <div class="codewrapper sourceCode" id="cb92">
 <h3 class="code-label">R<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -3676,7 +3676,7 @@ <h4 class="accordion-header" id="headingSolution9">
   Solution to Challenge 3
   </h4>
 </button>
-<div id="collapseSolution9" class="accordion-collapse collapse" aria-labelledby="headingSolution9" data-bs-parent="#accordionSolution9">
+<div id="collapseSolution9" class="accordion-collapse collapse" data-bs-parent="#accordionSolution9" aria-labelledby="headingSolution9">
 <div class="accordion-body">
 <p>You get the names of an object by wrapping the object name inside
 <code>names(...)</code>. Similarly, you get the data type of the names
@@ -3723,7 +3723,7 @@ <h4 class="accordion-header" id="headingSolution10">
   Solution to Challenge 4
   </h4>
 </button>
-<div id="collapseSolution10" class="accordion-collapse collapse" aria-labelledby="headingSolution10" data-bs-parent="#accordionSolution10">
+<div id="collapseSolution10" class="accordion-collapse collapse" data-bs-parent="#accordionSolution10" aria-labelledby="headingSolution10">
 <div class="accordion-body">
 <pre><code><span><span class="va">letter_no</span> <span class="op">&lt;-</span> <span class="fl">1</span><span class="op">:</span><span class="fl">26</span>   <span class="co"># or seq(1,26)</span></span>
 <span><span class="fu">names</span><span class="op">(</span><span class="va">letter_no</span><span class="op">)</span> <span class="op">&lt;-</span> <span class="va">LETTERS</span></span>
@@ -3917,7 +3917,7 @@ <h4 class="accordion-header" id="headingSolution11">
   Solution to Challenge 5
   </h4>
 </button>
-<div id="collapseSolution11" class="accordion-collapse collapse" aria-labelledby="headingSolution11" data-bs-parent="#accordionSolution11">
+<div id="collapseSolution11" class="accordion-collapse collapse" data-bs-parent="#accordionSolution11" aria-labelledby="headingSolution11">
 <div class="accordion-body">
 <div class="codewrapper sourceCode" id="cb138">
 <h3 class="code-label">R<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -4180,7 +4180,7 @@ <h4 class="accordion-header" id="headingSolution12">
   Solution to Challenge 6
   </h4>
 </button>
-<div id="collapseSolution12" class="accordion-collapse collapse" aria-labelledby="headingSolution12" data-bs-parent="#accordionSolution12">
+<div id="collapseSolution12" class="accordion-collapse collapse" data-bs-parent="#accordionSolution12" aria-labelledby="headingSolution12">
 <div class="accordion-body">
 <p>What do you think will be the result of
 <code>length(matrix_example)</code>?</p>
@@ -4226,7 +4226,7 @@ <h4 class="accordion-header" id="headingSolution13">
   Solution to Challenge 7
   </h4>
 </button>
-<div id="collapseSolution13" class="accordion-collapse collapse" aria-labelledby="headingSolution13" data-bs-parent="#accordionSolution13">
+<div id="collapseSolution13" class="accordion-collapse collapse" data-bs-parent="#accordionSolution13" aria-labelledby="headingSolution13">
 <div class="accordion-body">
 <p>Make another matrix, this time containing the numbers 1:50, with 5
 columns and 10 rows. Did the <code>matrix</code> function fill your
@@ -4270,7 +4270,7 @@ <h4 class="accordion-header" id="headingSolution14">
   Solution to Challenge 8
   </h4>
 </button>
-<div id="collapseSolution14" class="accordion-collapse collapse" aria-labelledby="headingSolution14" data-bs-parent="#accordionSolution14">
+<div id="collapseSolution14" class="accordion-collapse collapse" data-bs-parent="#accordionSolution14" aria-labelledby="headingSolution14">
 <div class="accordion-body">
 <div class="codewrapper sourceCode" id="cb173">
 <h3 class="code-label">R<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -4324,7 +4324,7 @@ <h4 class="accordion-header" id="headingSolution15">
   Solution to Challenge 9
   </h4>
 </button>
-<div id="collapseSolution15" class="accordion-collapse collapse" aria-labelledby="headingSolution15" data-bs-parent="#accordionSolution15">
+<div id="collapseSolution15" class="accordion-collapse collapse" data-bs-parent="#accordionSolution15" aria-labelledby="headingSolution15">
 <div class="accordion-body">
 <p>Consider the R output of the matrix below:</p>
 <div class="codewrapper">
@@ -4369,7 +4369,7 @@ <h3 class="callout-title">Key Points<a class="anchor" aria-label="anchor" href="
 </div>
 </section></section><section id="aio-05-data-structures-part2"><p>Content from <a href="05-data-structures-part2.html">Exploring Data Frames</a></p>
 <hr>
-<p>Last updated on 2024-07-02 |
+<p>Last updated on 2024-08-06 |
 
         <a href="https://github.com/UCL/ClinicianCoders/edit/main/episodes/05-data-structures-part2.Rmd" class="external-link">Edit this page <i aria-hidden="true" data-feather="edit"></i></a></p>
 <p>Estimated time: <i aria-hidden="true" data-feather="clock"></i> 30 minutes</p>
@@ -5136,7 +5136,7 @@ <h3 class="callout-title">Key Points<a class="anchor" aria-label="anchor" href="
 </div>
 </section></section><section id="aio-06-data-subsetting"><p>Content from <a href="06-data-subsetting.html">Subsetting Data</a></p>
 <hr>
-<p>Last updated on 2024-07-02 |
+<p>Last updated on 2024-08-06 |
 
         <a href="https://github.com/UCL/ClinicianCoders/edit/main/episodes/06-data-subsetting.Rmd" class="external-link">Edit this page <i aria-hidden="true" data-feather="edit"></i></a></p>
 <p>Estimated time: <i aria-hidden="true" data-feather="clock"></i> 50 minutes</p>
@@ -5477,7 +5477,7 @@ <h4 class="accordion-header" id="headingSolution1">
   Solution to challenge 1
   </h4>
 </button>
-<div id="collapseSolution1" class="accordion-collapse collapse" data-bs-parent="#accordionSolution1" aria-labelledby="headingSolution1">
+<div id="collapseSolution1" class="accordion-collapse collapse" aria-labelledby="headingSolution1" data-bs-parent="#accordionSolution1">
 <div class="accordion-body">
 <div class="codewrapper sourceCode" id="cb34">
 <h3 class="code-label">R<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -5674,7 +5674,7 @@ <h4 class="accordion-header" id="headingSolution2">
   Solution to challenge 2
   </h4>
 </button>
-<div id="collapseSolution2" class="accordion-collapse collapse" data-bs-parent="#accordionSolution2" aria-labelledby="headingSolution2">
+<div id="collapseSolution2" class="accordion-collapse collapse" aria-labelledby="headingSolution2" data-bs-parent="#accordionSolution2">
 <div class="accordion-body">
 <div class="codewrapper sourceCode" id="cb50">
 <h3 class="code-label">R<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -5932,7 +5932,7 @@ <h4 class="accordion-header" id="headingSolution3">
   Solution to challenge 3
   </h4>
 </button>
-<div id="collapseSolution3" class="accordion-collapse collapse" data-bs-parent="#accordionSolution3" aria-labelledby="headingSolution3">
+<div id="collapseSolution3" class="accordion-collapse collapse" aria-labelledby="headingSolution3" data-bs-parent="#accordionSolution3">
 <div class="accordion-body">
 <ul>
 <li>The <strong>wrong</strong> way to do this problem is
@@ -6228,7 +6228,7 @@ <h4 class="accordion-header" id="headingSolution4">
   Solution to challenge 4
   </h4>
 </button>
-<div id="collapseSolution4" class="accordion-collapse collapse" data-bs-parent="#accordionSolution4" aria-labelledby="headingSolution4">
+<div id="collapseSolution4" class="accordion-collapse collapse" aria-labelledby="headingSolution4" data-bs-parent="#accordionSolution4">
 <div class="accordion-body">
 <p>D</p>
 </div>
@@ -6377,7 +6377,7 @@ <h4 class="accordion-header" id="headingSolution5">
   Solution to challenge 5
   </h4>
 </button>
-<div id="collapseSolution5" class="accordion-collapse collapse" data-bs-parent="#accordionSolution5" aria-labelledby="headingSolution5">
+<div id="collapseSolution5" class="accordion-collapse collapse" aria-labelledby="headingSolution5" data-bs-parent="#accordionSolution5">
 <div class="accordion-body">
 <div class="codewrapper sourceCode" id="cb115">
 <h3 class="code-label">R<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -6443,7 +6443,7 @@ <h4 class="accordion-header" id="headingSolution6">
   Solution to challenge 6
   </h4>
 </button>
-<div id="collapseSolution6" class="accordion-collapse collapse" data-bs-parent="#accordionSolution6" aria-labelledby="headingSolution6">
+<div id="collapseSolution6" class="accordion-collapse collapse" aria-labelledby="headingSolution6" data-bs-parent="#accordionSolution6">
 <div class="accordion-body">
 <div class="codewrapper sourceCode" id="cb122">
 <h3 class="code-label">R<i aria-hidden="true" data-feather="chevron-left"></i><i aria-hidden="true" data-feather="chevron-right"></i>
@@ -6611,7 +6611,7 @@ <h4 class="accordion-header" id="headingSolution7">
   Solution to challenge 7
   </h4>
 </button>
-<div id="collapseSolution7" class="accordion-collapse collapse" data-bs-parent="#accordionSolution7" aria-labelledby="headingSolution7">
+<div id="collapseSolution7" class="accordion-collapse collapse" aria-labelledby="headingSolution7" data-bs-parent="#accordionSolution7">
 <div class="accordion-body">
 <p>Fix each of the following common data frame subsetting errors:</p>
 <ol style="list-style-type: decimal">
@@ -6697,7 +6697,7 @@ <h4 class="accordion-header" id="headingSolution8">
   Solution to challenge 8
   </h4>
 </button>
-<div id="collapseSolution8" class="accordion-collapse collapse" data-bs-parent="#accordionSolution8" aria-labelledby="headingSolution8">
+<div id="collapseSolution8" class="accordion-collapse collapse" aria-labelledby="headingSolution8" data-bs-parent="#accordionSolution8">
 <div class="accordion-body">
 <ol style="list-style-type: decimal">
 <li><p><code>gapminder</code> is a data.frame so needs to be subsetted
@@ -6737,7 +6737,7 @@ <h3 class="callout-title">Key Points<a class="anchor" aria-label="anchor" href="
 </div>
 </section></section><section id="aio-08-plot-ggplot2"><p>Content from <a href="08-plot-ggplot2.html">Creating Publication-Quality Graphics with ggplot2</a></p>
 <hr>
-<p>Last updated on 2024-07-02 |
+<p>Last updated on 2024-08-06 |
 
         <a href="https://github.com/UCL/ClinicianCoders/edit/main/episodes/08-plot-ggplot2.Rmd" class="external-link">Edit this page <i aria-hidden="true" data-feather="edit"></i></a></p>
 <p>Estimated time: <i aria-hidden="true" data-feather="clock"></i> 80 minutes</p>
@@ -6881,7 +6881,7 @@ <h4 class="accordion-header" id="headingSolution1">
   Solution to challenge 1
   </h4>
 </button>
-<div id="collapseSolution1" class="accordion-collapse collapse" aria-labelledby="headingSolution1" data-bs-parent="#accordionSolution1">
+<div id="collapseSolution1" class="accordion-collapse collapse" data-bs-parent="#accordionSolution1" aria-labelledby="headingSolution1">
 <div class="accordion-body">
 <p>Here is one possible solution:</p>
 <div class="codewrapper sourceCode" id="cb5">
@@ -6923,7 +6923,7 @@ <h4 class="accordion-header" id="headingSolution2">
   Solution to challenge 2
   </h4>
 </button>
-<div id="collapseSolution2" class="accordion-collapse collapse" aria-labelledby="headingSolution2" data-bs-parent="#accordionSolution2">
+<div id="collapseSolution2" class="accordion-collapse collapse" data-bs-parent="#accordionSolution2" aria-labelledby="headingSolution2">
 <div class="accordion-body">
 <p>The solution presented below adds <code>color=continent</code> to the
 call of the <code>aes</code> function. The general trend seems to
@@ -7037,7 +7037,7 @@ <h4 class="accordion-header" id="headingSolution3">
   Solution to challenge 3
   </h4>
 </button>
-<div id="collapseSolution3" class="accordion-collapse collapse" aria-labelledby="headingSolution3" data-bs-parent="#accordionSolution3">
+<div id="collapseSolution3" class="accordion-collapse collapse" data-bs-parent="#accordionSolution3" aria-labelledby="headingSolution3">
 <div class="accordion-body">
 <p>The lines now get drawn over the points!</p>
 <div class="codewrapper sourceCode" id="cb11">
@@ -7171,7 +7171,7 @@ <h4 class="accordion-header" id="headingSolution4">
   Solution to challenge 4a
   </h4>
 </button>
-<div id="collapseSolution4" class="accordion-collapse collapse" aria-labelledby="headingSolution4" data-bs-parent="#accordionSolution4">
+<div id="collapseSolution4" class="accordion-collapse collapse" data-bs-parent="#accordionSolution4" aria-labelledby="headingSolution4">
 <div class="accordion-body">
 <p>Here a possible solution: Notice that the <code>color</code> argument
 is supplied outside of the <code>aes()</code> function. This means that
@@ -7216,7 +7216,7 @@ <h4 class="accordion-header" id="headingSolution5">
   Solution to challenge 4b
   </h4>
 </button>
-<div id="collapseSolution5" class="accordion-collapse collapse" aria-labelledby="headingSolution5" data-bs-parent="#accordionSolution5">
+<div id="collapseSolution5" class="accordion-collapse collapse" data-bs-parent="#accordionSolution5" aria-labelledby="headingSolution5">
 <div class="accordion-body">
 <p>Here is a possible solution: Notice that supplying the
 <code>color</code> argument inside the <code>aes()</code> functions
@@ -7379,7 +7379,7 @@ <h4 class="accordion-header" id="headingSolution6">
   Solution to Challenge 5
   </h4>
 </button>
-<div id="collapseSolution6" class="accordion-collapse collapse" aria-labelledby="headingSolution6" data-bs-parent="#accordionSolution6">
+<div id="collapseSolution6" class="accordion-collapse collapse" data-bs-parent="#accordionSolution6" aria-labelledby="headingSolution6">
 <div class="accordion-body">
 <p>Here a possible solution: <code>xlab()</code> and <code>ylab()</code>
 set labels for the x and y axes, respectively The axis title, text and
@@ -7419,7 +7419,7 @@ <h3 class="callout-title">Key Points<a class="anchor" aria-label="anchor" href="
 </div>
 </section></section><section id="aio-11-writing-data"><p>Content from <a href="11-writing-data.html">Writing Data</a></p>
 <hr>
-<p>Last updated on 2024-07-02 |
+<p>Last updated on 2024-08-06 |
 
         <a href="https://github.com/UCL/ClinicianCoders/edit/main/episodes/11-writing-data.Rmd" class="external-link">Edit this page <i aria-hidden="true" data-feather="edit"></i></a></p>
 <p>Estimated time: <i aria-hidden="true" data-feather="clock"></i> 20 minutes</p>
@@ -7672,7 +7672,7 @@ <h3 class="callout-title">Key Points<a class="anchor" aria-label="anchor" href="
 </div>
 </section></section><section id="aio-12-dplyr"><p>Content from <a href="12-dplyr.html">Data Frame Manipulation with dplyr</a></p>
 <hr>
-<p>Last updated on 2024-07-02 |
+<p>Last updated on 2024-08-06 |
 
         <a href="https://github.com/UCL/ClinicianCoders/edit/main/episodes/12-dplyr.Rmd" class="external-link">Edit this page <i aria-hidden="true" data-feather="edit"></i></a></p>
 <p>Estimated time: <i aria-hidden="true" data-feather="clock"></i> 55 minutes</p>
@@ -8494,7 +8494,7 @@ <h3 class="callout-title">Key Points<a class="anchor" aria-label="anchor" href="
 </div>
 </section></section><section id="aio-13-tidyr"><p>Content from <a href="13-tidyr.html">Data Frame Manipulation with tidyr</a></p>
 <hr>
-<p>Last updated on 2024-07-02 |
+<p>Last updated on 2024-08-06 |
 
         <a href="https://github.com/UCL/ClinicianCoders/edit/main/episodes/13-tidyr.Rmd" class="external-link">Edit this page <i aria-hidden="true" data-feather="edit"></i></a></p>
 <p>Estimated time: <i aria-hidden="true" data-feather="clock"></i> 45 minutes</p>
@@ -9230,7 +9230,7 @@ <h3 class="callout-title">Key Points<a class="anchor" aria-label="anchor" href="
 </div>
 </section></section><section id="aio-statistics"><p>Content from <a href="statistics.html">Basic Statistics: describing, modelling and reporting</a></p>
 <hr>
-<p>Last updated on 2024-07-02 |
+<p>Last updated on 2024-08-06 |
 
         <a href="https://github.com/UCL/ClinicianCoders/edit/main/episodes/statistics.Rmd" class="external-link">Edit this page <i aria-hidden="true" data-feather="edit"></i></a></p>
 <p>Estimated time: <i aria-hidden="true" data-feather="clock"></i> 80 minutes</p>
@@ -9313,12 +9313,21 @@ <h3 class="code-label">R<i aria-hidden="true" data-feather="chevron-left"></i><i
 <a class="anchor" aria-label="anchor" href="#descriptive-and-inferential-statistics"></a>
 </h2>
 <hr class="half-width">
-<div class="Background">
+<div id="callout1" class="callout">
+<div class="callout-square">
+<i class="callout-icon" data-feather="bell"></i>
+</div>
+<div class="callout-inner">
+<h3 class="callout-title">Callout<a class="anchor" aria-label="anchor" href="#callout1"></a>
+</h3>
+<div class="callout-content">
 <p>Just as data in general are of different types - for example numeric
 vs text data - statistical data are assigned to different <em>levels of
 measure</em>. The level of measure determines how we can describe and
 model the data.</p>
 </div>
+</div>
+</div>
 </section><div class="section level1">
 <h1 id="describing-data">Describing data<a class="anchor" aria-label="anchor" href="#describing-data"></a>
 </h1>
@@ -9326,12 +9335,12 @@ <h1 id="describing-data">Describing data<a class="anchor" aria-label="anchor" hr
 <li>Continuous variables</li>
 <li>Discrete variables</li>
 </ul>
-<div id="callout1" class="callout">
+<div id="callout2" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
 <div class="callout-inner">
-<h3 class="callout-title">Callout<a class="anchor" aria-label="anchor" href="#callout1"></a>
+<h3 class="callout-title">Callout<a class="anchor" aria-label="anchor" href="#callout2"></a>
 </h3>
 <div class="callout-content">
 <p>How do we convey information on what your data looks like, using
@@ -9610,8 +9619,8 @@ <h3 class="code-label">R<i aria-hidden="true" data-feather="chevron-left"></i><i
 </h3>
 <pre class="downlit sourceCode r">
 <code class="sourceCode R"><span><span class="fu">table</span><span class="op">(</span></span>
-<span>    <span class="va">gapminder</span><span class="op">$</span><span class="va">country</span><span class="op">[</span><span class="va">gapminder</span><span class="op">$</span><span class="va">year</span> <span class="op">==</span> <span class="fl">2007</span><span class="op">]</span>,</span>
-<span>    <span class="va">gapminder</span><span class="op">$</span><span class="va">continent</span><span class="op">[</span><span class="va">gapminder</span><span class="op">$</span><span class="va">year</span> <span class="op">==</span> <span class="fl">2007</span><span class="op">]</span></span>
+<span>  <span class="va">gapminder</span><span class="op">$</span><span class="va">country</span><span class="op">[</span><span class="va">gapminder</span><span class="op">$</span><span class="va">year</span> <span class="op">==</span> <span class="fl">2007</span><span class="op">]</span>,</span>
+<span>  <span class="va">gapminder</span><span class="op">$</span><span class="va">continent</span><span class="op">[</span><span class="va">gapminder</span><span class="op">$</span><span class="va">year</span> <span class="op">==</span> <span class="fl">2007</span><span class="op">]</span></span>
 <span><span class="op">)</span></span></code></pre>
 </div>
 <div class="codewrapper">
@@ -9775,12 +9784,12 @@ <h2 id="meaningful-analysis">Meaningful analysis<a class="anchor" aria-label="an
 <ul>
 <li>What is your hypothesis - what is your null hypothesis?</li>
 </ul>
-<div id="callout2" class="callout">
+<div id="callout3" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
 <div class="callout-inner">
-<h3 class="callout-title">Callout<a class="anchor" aria-label="anchor" href="#callout2"></a>
+<h3 class="callout-title">Callout<a class="anchor" aria-label="anchor" href="#callout3"></a>
 </h3>
 <div class="callout-content">
 <p>Always: the level of the independent variable has no effect on the
@@ -10163,7 +10172,7 @@ <h2 id="lunch">Lunch<a class="anchor" aria-label="anchor" href="#lunch"></a>
 </div>
 </div></section><section id="aio-14-knitr-markdown"><p>Content from <a href="14-knitr-markdown.html">Producing Reports With knitr</a></p>
 <hr>
-<p>Last updated on 2024-07-02 |
+<p>Last updated on 2024-08-06 |
 
         <a href="https://github.com/UCL/ClinicianCoders/edit/main/episodes/14-knitr-markdown.Rmd" class="external-link">Edit this page <i aria-hidden="true" data-feather="edit"></i></a></p>
 <p>Estimated time: <i aria-hidden="true" data-feather="clock"></i> 75 minutes</p>
@@ -10358,7 +10367,7 @@ <h4 class="accordion-header" id="headingSolution1">
   Solution to Challenge 1
   </h4>
 </button>
-<div id="collapseSolution1" class="accordion-collapse collapse" aria-labelledby="headingSolution1" data-bs-parent="#accordionSolution1">
+<div id="collapseSolution1" class="accordion-collapse collapse" data-bs-parent="#accordionSolution1" aria-labelledby="headingSolution1">
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 <p>In RStudio, select File &gt; New file &gt; R Markdown…</p>
 <p>Delete the placeholder text and add the following:</p>
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   Solution to Challenge 2
   </h4>
 </button>
-<div id="collapseSolution2" class="accordion-collapse collapse" aria-labelledby="headingSolution2" data-bs-parent="#accordionSolution2">
+<div id="collapseSolution2" class="accordion-collapse collapse" data-bs-parent="#accordionSolution2" aria-labelledby="headingSolution2">
 <div class="accordion-body">
 <pre>
 ```{r load-ggplot2}
@@ -10537,7 +10546,7 @@ <h4 class="accordion-header" id="headingSolution3">
   Solution to Challenge 3
   </h4>
 </button>
-<div id="collapseSolution3" class="accordion-collapse collapse" aria-labelledby="headingSolution3" data-bs-parent="#accordionSolution3">
+<div id="collapseSolution3" class="accordion-collapse collapse" data-bs-parent="#accordionSolution3" aria-labelledby="headingSolution3">
 <div class="accordion-body">
 <pre>
 ```{r echo = FALSE, fig.width = 3}
@@ -10589,7 +10598,7 @@ <h4 class="accordion-header" id="headingSolution4">
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   </h4>
 </button>
-<div id="collapseSolution4" class="accordion-collapse collapse" aria-labelledby="headingSolution4" data-bs-parent="#accordionSolution4">
+<div id="collapseSolution4" class="accordion-collapse collapse" data-bs-parent="#accordionSolution4" aria-labelledby="headingSolution4">
 <div class="accordion-body">
 <p>Here’s some inline code to determine that 2 + 2 = <code>4</code>.</p>
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@@ -10688,7 +10697,7 @@ <h3 class="callout-title">Key Points<a class="anchor" aria-label="anchor" href="
 </div>
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 <hr>
-<p>Last updated on 2024-07-02 |
+<p>Last updated on 2024-08-06 |
 
         <a href="https://github.com/UCL/ClinicianCoders/edit/main/episodes/15-wrap-up.Rmd" class="external-link">Edit this page <i aria-hidden="true" data-feather="edit"></i></a></p>
 <p>Estimated time: <i aria-hidden="true" data-feather="clock"></i> 15 minutes</p>
diff --git a/instructor/discuss.html b/instructor/discuss.html
index 3740ff342..44ee9127a 100644
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-        <p>Last updated on 2024-07-02 |
+        <p>Last updated on 2024-08-06 |
 
         <a href="https://github.com/UCL/ClinicianCoders/edit/main/learners/discuss.md" class="external-link">Edit this page <i aria-hidden="true" data-feather="edit"></i></a></p>
 
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index 7f6fc800f..9e586855d 100644
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-        <p>Last updated on 2024-07-02 |
+        <p>Last updated on 2024-08-06 |
 
         <a href="https://github.com/UCL/ClinicianCoders/edit/main/learners/reference.md" class="external-link">Edit this page <i aria-hidden="true" data-feather="edit"></i></a></p>
 
@@ -951,7 +951,7 @@ <h1>Reference</h1>
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diff --git a/instructor/statistics.html b/instructor/statistics.html
index 4d9701cd2..726e1733e 100644
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+++ b/instructor/statistics.html
@@ -382,7 +382,7 @@ <h2 class="accordion-header" id="flush-headingTwelve">
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         <h1>Basic Statistics: describing, modelling and reporting</h1>
-        <p>Last updated on 2024-07-02 |
+        <p>Last updated on 2024-08-06 |
 
         <a href="https://github.com/UCL/ClinicianCoders/edit/main/episodes/statistics.Rmd" class="external-link">Edit this page <i aria-hidden="true" data-feather="edit"></i></a></p>
 
@@ -456,22 +456,31 @@ <h3 class="code-label">R<i aria-hidden="true" data-feather="chevron-left"></i><i
 ensure <strong>representative</strong> data.</li>
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 <a class="anchor" aria-label="anchor" href="#descriptive-and-inferential-statistics"></a></h2>
-<hr class="half-width"><div class="Background">
+<hr class="half-width"><div id="callout1" class="callout">
+<div class="callout-square">
+<i class="callout-icon" data-feather="bell"></i>
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+<div class="callout-inner">
+<h3 class="callout-title">Callout<a class="anchor" aria-label="anchor" href="#callout1"></a>
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+<div class="callout-content">
 <p>Just as data in general are of different types - for example numeric
 vs text data - statistical data are assigned to different <em>levels of
 measure</em>. The level of measure determines how we can describe and
 model the data.</p>
 </div>
+</div>
+</div>
 </section><div class="section level1">
 <h1 id="describing-data">Describing data<a class="anchor" aria-label="anchor" href="#describing-data"></a></h1>
 <ul><li>Continuous variables</li>
 <li>Discrete variables</li>
-</ul><div id="callout1" class="callout">
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 <p>How do we convey information on what your data looks like, using
@@ -724,8 +733,8 @@ <h3 class="code-label">R<i aria-hidden="true" data-feather="chevron-left"></i><i
 </h3>
 <pre class="downlit sourceCode r">
 <code class="sourceCode R"><span><span class="fu">table</span><span class="op">(</span></span>
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+<span>  <span class="va">gapminder</span><span class="op">$</span><span class="va">country</span><span class="op">[</span><span class="va">gapminder</span><span class="op">$</span><span class="va">year</span> <span class="op">==</span> <span class="fl">2007</span><span class="op">]</span>,</span>
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 <div class="section level2">
 <h2 id="meaningful-analysis">Meaningful analysis<a class="anchor" aria-label="anchor" href="#meaningful-analysis"></a></h2>
 <ul><li>What is your hypothesis - what is your null hypothesis?</li>
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   "dateCreated": "2023-10-26",
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diff --git a/pkgdown.yml b/pkgdown.yml
index 71d04a7eb..d7f7d8d8a 100644
--- a/pkgdown.yml
+++ b/pkgdown.yml
@@ -2,4 +2,4 @@ pandoc: 3.1.11
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diff --git a/reference.html b/reference.html
index 401c61e43..4f04c997c 100644
--- a/reference.html
+++ b/reference.html
@@ -368,7 +368,7 @@ <h2 class="accordion-header" id="flush-headingTwelve">
       </div>
       <hr></nav><main id="main-content" class="main-content"><div class="container lesson-content">
         <h1>Reference</h1>
-        <p>Last updated on 2024-07-02 |
+        <p>Last updated on 2024-08-06 |
 
         <a href="https://github.com/UCL/ClinicianCoders/edit/main/learners/reference.md" class="external-link">Edit this page <i aria-hidden="true" data-feather="edit"></i></a></p>
 
@@ -949,7 +949,7 @@ <h1>Reference</h1>
   "url": "https://UCL.github.io/ClinicianCoders/reference.html",
   "identifier": "https://UCL.github.io/ClinicianCoders/reference.html",
   "dateCreated": "2023-10-26",
-  "dateModified": "2024-07-02",
+  "dateModified": "2024-08-06",
   "datePublished": "2024-08-06"
 }
 
diff --git a/statistics.html b/statistics.html
index bcbd5febb..890ddc421 100644
--- a/statistics.html
+++ b/statistics.html
@@ -382,7 +382,7 @@ <h2 class="accordion-header" id="flush-headingTwelve">
       </div>
       <hr></nav><main id="main-content" class="main-content"><div class="container lesson-content">
         <h1>Basic Statistics: describing, modelling and reporting</h1>
-        <p>Last updated on 2024-07-02 |
+        <p>Last updated on 2024-08-06 |
 
         <a href="https://github.com/UCL/ClinicianCoders/edit/main/episodes/statistics.Rmd" class="external-link">Edit this page <i aria-hidden="true" data-feather="edit"></i></a></p>
 
@@ -454,22 +454,31 @@ <h3 class="code-label">R<i aria-hidden="true" data-feather="chevron-left"></i><i
 ensure <strong>representative</strong> data.</li>
 </ul></section><section><h2 class="section-heading" id="descriptive-and-inferential-statistics">Descriptive and inferential statistics<a class="anchor" aria-label="anchor" href="#descriptive-and-inferential-statistics"></a>
 <a class="anchor" aria-label="anchor" href="#descriptive-and-inferential-statistics"></a></h2>
-<hr class="half-width"><div class="Background">
+<hr class="half-width"><div id="callout1" class="callout">
+<div class="callout-square">
+<i class="callout-icon" data-feather="bell"></i>
+</div>
+<div class="callout-inner">
+<h3 class="callout-title">Callout<a class="anchor" aria-label="anchor" href="#callout1"></a>
+</h3>
+<div class="callout-content">
 <p>Just as data in general are of different types - for example numeric
 vs text data - statistical data are assigned to different <em>levels of
 measure</em>. The level of measure determines how we can describe and
 model the data.</p>
 </div>
+</div>
+</div>
 </section><div class="section level1">
 <h1 id="describing-data">Describing data<a class="anchor" aria-label="anchor" href="#describing-data"></a></h1>
 <ul><li>Continuous variables</li>
 <li>Discrete variables</li>
-</ul><div id="callout1" class="callout">
+</ul><div id="callout2" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
 <div class="callout-inner">
-<h3 class="callout-title">Callout<a class="anchor" aria-label="anchor" href="#callout1"></a>
+<h3 class="callout-title">Callout<a class="anchor" aria-label="anchor" href="#callout2"></a>
 </h3>
 <div class="callout-content">
 <p>How do we convey information on what your data looks like, using
@@ -697,8 +706,8 @@ <h3 class="code-label">R<i aria-hidden="true" data-feather="chevron-left"></i><i
 </h3>
 <pre class="downlit sourceCode r">
 <code class="sourceCode R"><span><span class="fu">table</span><span class="op">(</span></span>
-<span>    <span class="va">gapminder</span><span class="op">$</span><span class="va">country</span><span class="op">[</span><span class="va">gapminder</span><span class="op">$</span><span class="va">year</span> <span class="op">==</span> <span class="fl">2007</span><span class="op">]</span>,</span>
-<span>    <span class="va">gapminder</span><span class="op">$</span><span class="va">continent</span><span class="op">[</span><span class="va">gapminder</span><span class="op">$</span><span class="va">year</span> <span class="op">==</span> <span class="fl">2007</span><span class="op">]</span></span>
+<span>  <span class="va">gapminder</span><span class="op">$</span><span class="va">country</span><span class="op">[</span><span class="va">gapminder</span><span class="op">$</span><span class="va">year</span> <span class="op">==</span> <span class="fl">2007</span><span class="op">]</span>,</span>
+<span>  <span class="va">gapminder</span><span class="op">$</span><span class="va">continent</span><span class="op">[</span><span class="va">gapminder</span><span class="op">$</span><span class="va">year</span> <span class="op">==</span> <span class="fl">2007</span><span class="op">]</span></span>
 <span><span class="op">)</span></span></code></pre>
 </div>
 <div class="codewrapper">
@@ -858,12 +867,12 @@ <h1 id="inferential-statistics">Inferential statistics<a class="anchor" aria-lab
 <div class="section level2">
 <h2 id="meaningful-analysis">Meaningful analysis<a class="anchor" aria-label="anchor" href="#meaningful-analysis"></a></h2>
 <ul><li>What is your hypothesis - what is your null hypothesis?</li>
-</ul><div id="callout2" class="callout">
+</ul><div id="callout3" class="callout">
 <div class="callout-square">
 <i class="callout-icon" data-feather="bell"></i>
 </div>
 <div class="callout-inner">
-<h3 class="callout-title">Callout<a class="anchor" aria-label="anchor" href="#callout2"></a>
+<h3 class="callout-title">Callout<a class="anchor" aria-label="anchor" href="#callout3"></a>
 </h3>
 <div class="callout-content">
 <p>Always: the level of the independent variable has no effect on the
@@ -1275,7 +1284,7 @@ <h2 id="lunch">Lunch<a class="anchor" aria-label="anchor" href="#lunch"></a></h2
   "url": "https://UCL.github.io/ClinicianCoders/statistics.html",
   "identifier": "https://UCL.github.io/ClinicianCoders/statistics.html",
   "dateCreated": "2023-10-26",
-  "dateModified": "2024-07-02",
+  "dateModified": "2024-08-06",
   "datePublished": "2024-08-06"
 }