Issues with random effects: estimate_slopes and estimate_contrasts fa…

…ilures using the marginaleffects backend (#410)

* Issues with random effects: estimate_slopes and estimate_contrasts failures using the marginaleffects backend
Fixes #409

* add tests

* news

* update tests

DESCRIPTION

@@ -1,7 +1,7 @@
 Type: Package
 Package: modelbased
 Title: Estimation of Model-Based Predictions, Contrasts and Means
-Version: 0.9.0.25
+Version: 0.9.0.26
 Authors@R:
     c(person(given = "Dominique",
              family = "Makowski",

NEWS.md

@@ -54,6 +54,8 @@
 
 * Fixed issues with contrasting slopes when `backend` was `"emmeans"`.
 
+* Fixed issue in `estimate_slopes()` for models from package *lme4*.
+
 # modelbased 0.9.0
 
 ## Breaking Changes

R/get_marginaltrends.R

@@ -31,10 +31,15 @@ get_marginaltrends <- function(model,
   if (is.null(by)) {
     datagrid <- datagrid_info <- NULL
   } else {
-    # setup arguments
-    dg_args <- list(model, by = by, verbose = FALSE)
+    dg_args <- list(
+      model,
+      by = by,
+      factors = "all",
+      include_random = TRUE,
+      verbose = FALSE
+    )
     # add user-arguments from "...", but remove those arguments that are already set
-    dots[c("by", "verbose")] <- NULL
+    dots[c("by", "factors", "include_random", "verbose")] <- NULL
     dg_args <- insight::compact_list(c(dg_args, dots))
 
     # Get corresponding datagrid (and deal with particular ats)

inst/WORDLIST

@@ -104,6 +104,8 @@ intra
 io
 jmr
 lifecycle
+lme
+lme4
 loess
 marginaleffects
 marginalizations

tests/testthat/test-estimate_slopes.R

@@ -93,3 +93,44 @@ test_that("estimate_slopes, custom comparison", {
   expect_identical(dim(out), c(1L, 7L))
   expect_equal(out$Difference, -0.08782885, tolerance = 1e-4)
 })
+
+skip_on_cran()
+
+test_that("estimate_slopes, works with lme4", {
+  skip_if_not_installed("lme4")
+  data(CO2)
+  model_lme4 <- suppressWarnings(lme4::lmer(
+    uptake ~ conc * Plant + Treatment + (1 | Type),
+    data = CO2
+  ))
+  out <- estimate_slopes(model_lme4, trend = "conc", by = "Plant")
+  expect_identical(dim(out), c(12L, 7L))
+  expect_equal(
+    out$Slope,
+    c(
+      0.01847, 0.02553, 0.02322, 0.02119, 0.02458, 0.02548, 0.01366,
+      0.01519, 0.02286, 0.00541, 0.00632, 0.01085
+    ),
+    tolerance = 1e-3
+  )
+})
+
+
+test_that("estimate_slopes, works with glmmTMB", {
+  skip_if_not_installed("glmmTMB")
+  data(CO2)
+  model_glmmTMB <- suppressWarnings(glmmTMB::glmmTMB(
+    uptake ~ conc * Plant + (1 | Type),
+    data = CO2
+  ))
+  out <- estimate_slopes(model_glmmTMB, trend = "conc", by = "Plant")
+  expect_identical(dim(out), c(12L, 7L))
+  expect_equal(
+    out$Slope,
+    c(
+      0.01847, 0.02553, 0.02322, 0.02119, 0.02458, 0.02548, 0.01366,
+      0.01519, 0.02286, 0.00541, 0.00632, 0.01085
+    ),
+    tolerance = 1e-3
+  )
+})