Returns the number of group levels of random effects from mixed models.
Arguments
- x
A mixed model.
- ...
Additional arguments that can be passed to the function. Currently, you can use
data
to provide the model data, if available, to avoid retrieving model data multiple times.
Examples
data(sleepstudy, package = "lme4")
set.seed(12345)
sleepstudy$grp <- sample(1:5, size = 180, replace = TRUE)
sleepstudy$subgrp <- NA
for (i in 1:5) {
filter_group <- sleepstudy$grp == i
sleepstudy$subgrp[filter_group] <-
sample(1:30, size = sum(filter_group), replace = TRUE)
}
model <- lme4::lmer(
Reaction ~ Days + (1 | grp / subgrp) + (1 | Subject),
data = sleepstudy
)
n_grouplevels(model)
#> Group | N_levels
#> ---------------------
#> subgrp | 30
#> grp | 5
#> Subject | 18
#> subgrp:grp | 108