initialize parameters_groupspecific #484 #482

NAMESPACE

@@ -905,6 +905,7 @@ export(p_value_robust)
 export(p_value_satterthwaite)
 export(p_value_wald)
 export(parameters)
+export(parameters_groupspecific)
 export(parameters_type)
 export(pool_parameters)
 export(principal_components)

R/parameters_grouplevel.R

@@ -0,0 +1,40 @@
+#' Extract group-specific parameters of mixed models
+#'
+#' Extract parameters of each individual group in the context of mixed models.
+#'
+#' @inheritParams model_parameters.merMod
+#'
+#' @examples
+#' library(parameters)
+#' if (require("lme4")) {
+#'   data <- lme4::sleepstudy
+#'
+#'   # Random intercept
+#'   model <- lmer(Reaction ~ Days + (1 | Subject), data = data)
+#'   parameters_groupspecific(model)
+#'
+#'   # Random slope and intercept
+#'   model <- lmer(Reaction ~ Days + (1 + Days  | Subject), data = data)
+#'   parameters_groupspecific(model)
+#'
+#'   # Nested random factors
+#'   set.seed(12345)
+#'   data$grp <- sample(1:5, size = 180, replace = TRUE)
+#'   data$subgrp <- NA
+#'   for (i in 1:5) {
+#'     filter_group <- data$grp == i
+#'     data$subgrp[filter_group] <- sample(1:30, size = sum(filter_group), replace = TRUE)
+#'   }
+#'   model <- lmer(Reaction ~ Days + (1 | grp / subgrp) + (1 | Subject), data = data)
+#'   parameters_groupspecific(model)
+#'
+#' }
+#' @export
+parameters_groupspecific <- function(model, ...) {
+  # Extract params
+  out <- model_parameters(model, effects = "random", group_level = TRUE)
+
+  # Assign new class
+  class(out) <- c("parmaeters_groupspecific", class(out))
+  out
+}