updates

DESCRIPTION

@@ -1,7 +1,7 @@
 Type: Package
 Package: performance
 Title: Assessment of Regression Models Performance
-Version: 0.12.2.4
+Version: 0.12.2.5
 Authors@R:
     c(person(given = "Daniel",
              family = "Lüdecke",

R/check_dag.R

@@ -12,7 +12,8 @@
 #'
 #' @param ... One or more formulas, which are converted into **dagitty** syntax.
 #' First element may also be model object. If a model objects is provided, its
-#' formula is used as first formula. See 'Details'.
+#' formula is used as first formula, and all independent variables will be used
+#' for the `adjusted` argument. See 'Details' and 'Examples'.
 #' @param outcome Name of the dependent variable (outcome), as character string.
 #' Must be a valid name from the formulas. If not set, the first dependent
 #' variable from the formulas is used.
@@ -21,7 +22,8 @@
 #' Must be a valid name from the formulas. If not set, the first independent
 #' variable from the formulas is used.
 #' @param adjusted A character vector with names of variables that are adjusted
-#' for in the model.
+#' for in the model. If a model object is provided in `...`, any values in
+#' `adjusted` will be overwritten by the model's independent variables.
 #' @param latent A character vector with names of latent variables in the model.
 #' @param effect Character string, indicating which effect to check. Can be
 #' `"all"` (default), `"total"`, or `"direct"`.
@@ -74,6 +76,18 @@
 #'
 #' # Objects returned by `check_dag()` can be used with "ggdag" or "dagitty"
 #' ggdag::ggdag_status(dag)
+#'
+#' # Using a model object to extract information about outcome,
+#' # exposure and adjusted variables
+#' data(mtcars)
+#' m <- lm(mpg ~ wt + gear + disp + cyl, data = mtcars)
+#' dag <- check_dag(
+#'   m,
+#'   wt ~ disp + cyl,
+#'   wt ~ am
+#' )
+#' dag
+#' plot(dag)
 #' @export
 check_dag <- function(...,
                       outcome = NULL,
@@ -124,6 +138,11 @@ check_dag.default <- function(...,
     formulas[[1]] <- stats::as.formula(
       paste(vars$response, "~", paste(vars$conditional, collapse = "+"))
     )
+    # if we have a model, we *always* overwrite adjusted
+    if (!is.null(adjusted)) {
+      insight::format_alert("The `adjusted` argument will be overwritten by all independent variables from the model.") # nolint
+    }
+    adjusted <- vars$conditional
   }
 
   # if outcome is not set, use first dependent variable
@@ -230,6 +249,16 @@ print.check_dag <- function(x, ...) {
       ": ", datawizard::text_concatenate(attributes(x)$exposure)
     )
 
+    # add information on adjustments
+    if (!is.null(out$current_adjustments)) {
+      exposure_outcome_text <- paste0(
+        exposure_outcome_text,
+        "\n- Adjustment",
+        ifelse(length(out$current_adjustments) > 1, "s", ""),
+        ": ", datawizard::text_concatenate(out$current_adjustments)
+      )
+    }
+
     # build message with check results for effects -----------------------
 
     if (isTRUE(out$adjustment_not_needed)) {

tests/testthat/_snaps/check_dag.md

@@ -30,6 +30,7 @@
       Model is correctly specified.
       - Outcome: y
       - Exposure: x
+      - Adjustment: b
       
       All minimal sufficient adjustments to estimate the direct effect were done.
       
@@ -38,6 +39,7 @@
       Model is correctly specified.
       - Outcome: y
       - Exposure: x
+      - Adjustment: b
       
       All minimal sufficient adjustments to estimate the total effect were done.
       
@@ -76,6 +78,7 @@
       Incorrectly adjusted!
       - Outcome: y
       - Exposure: x
+      - Adjustment: c
       
       To estimate the direct effect, also adjust for `b` and `c`.
       Currently, the model currently only adjusts for `c`.
@@ -85,8 +88,33 @@
       Incorrectly adjusted!
       - Outcome: y
       - Exposure: x
+      - Adjustment: c
       
       To estimate the total effect, also adjust for `b` and `c`.
       Currently, the model currently only adjusts for `c`.
       
 
+---
+
+    Code
+      print(dag)
+    Output
+      # Correct adjustments for identifying direct effects
+      
+      Model is correctly specified.
+      - Outcome: mpg
+      - Exposure: wt
+      - Adjustments: cyl, disp and gear
+      
+      All minimal sufficient adjustments to estimate the direct effect were done.
+      
+      # Correct adjustments for identifying total effects
+      
+      Model is correctly specified.
+      - Outcome: mpg
+      - Exposure: wt
+      - Adjustments: cyl, disp and gear
+      
+      All minimal sufficient adjustments to estimate the total effect were done.
+      
+

tests/testthat/test-check_dag.R

@@ -31,6 +31,15 @@ test_that("check_dag", {
     adjusted = "c"
   )
   expect_snapshot(print(dag))
+  data(mtcars)
+  m <- lm(mpg ~ wt + gear + disp + cyl, data = mtcars)
+  dag <- check_dag(
+    m,
+    wt ~ disp + cyl,
+    wt ~ am
+  )
+  dag
+  expect_snapshot(print(dag))
 })
 
 test_that("check_dag, cylic error", {