Summarize a Variable in a Long Dataset by ID

Summarize a Variable in a Long Dataset by ID

Usage

.summary.ID(data, var, idvar, CI = 0.95, robust = FALSE)

Arguments

data

A data.table object, long format

var

A character string, the name of the variable to summarize

idvar

A character string, the name of the grouping variable

CI

A numeric value, the confidence interval to use. Default is .95.

robust

A logical. Default is FALSE. If TRUE, the function will use the median as the estimate. If FALSE, the function will use the mean as the estimate.

Value

A data.table object with the mean/median, lower limit, and upper limit of the variable specified in var for each level of the grouping variable specified in idvar.