bruceR (version 0.7.2)

group_mean_center: Group-mean centering

Description

Compute group-mean centered variables. Usually used for HLM level-1 predictors.

Usage

group_mean_center(
  data,
  vars = setdiff(names(data), by),
  by,
  std = FALSE,
  add_suffix = "",
  add_group_mean = "_mean"
)

Arguments

data

Data object.

vars

Variable(s) to be centered.

by

Grouping variable.

std

Standardized or not. Default is FALSE.

add_suffix

The suffix of the centered variable(s). Default is "". You may set it to "_c", "_center", etc.

add_group_mean

The suffix of the variable name(s) of group means. Default is "_mean" (see Examples).

Value

A new data object containing the centered variable(s).

See Also

grand_mean_center

Examples

# NOT RUN {
d=data.table(x=1:9, g=rep(1:3, each=3))

d.c=group_mean_center(d, "x", by="g")
d.c

d.c=group_mean_center(d, "x", by="g", add_suffix="_c")
d.c

# }