check_staggered: check_staggered

In BMisc: Miscellaneous Functions for Panel Data, Quantiles, and Printing Results

check_staggered

Description

A function to check whether treatment is staggered in a panel data set; that is, whether treatment is absorbing, so that no unit ever reverts from treated back to untreated.

Usage

check_staggered(df, idname, treatname, tname = NULL)

Arguments

df	the data.frame used in the function
idname	name of column that holds the unit id
treatname	name of column with the treatment indicator
tname	name of column that holds the time period. If supplied, each unit's rows are sorted by it before checking. If 'NULL' (the default), the rows are assumed to already be in time order.

Value

a logical indicating whether treatment is staggered

Examples

n <- 50
id <- rep(seq_len(n), each = 4)
t <- rep(1:4, n)
g <- rep(sample(c(0, 2, 3), n, replace = TRUE), each = 4)
treat <- as.integer(t >= g & g > 0)
dta <- data.frame(id = id, t = t, treat = treat)
check_staggered(dta, idname = "id", treatname = "treat")

## treatment that switches back off is not staggered
dta_rev <- data.frame(
  id = c(1, 1, 2, 2), t = c(1, 2, 1, 2), treat = c(0, 1, 1, 0)
)
check_staggered(dta_rev, idname = "id", treatname = "treat")

BMisc documentation built on Aug. 22, 2026, 5:07 p.m.