Function to check if a variable is unique for all cases of an identifier variable. This is a fast and more efficient version of
checkUniqueness which always returns a logical, non missing value of length one.
Usage
checkUniqueness2(GADSdat, varName, idVar, impVar)
Arguments
- GADSdat
GADSdat object imported via eatGADS.
- varName
Single string containing the variable name for which the check should be performed.
- idVar
Single string containing the name of the identifier variable.
- impVar
Single string containing the name of the imputation number.
Value
Returns a logical of length one.
Details
For example if missing values are multiple imputed and data is stored in a long format, checking the uniqueness of a variable
within an identifier can be tricky. This function automates this task via reshaping the data into wide format and testing equality
among the reshaped variables. Similar functionality (via matrices) is covered by lme4::isNested,
which is more general and performs similarly.
Examples
## create an example GADSdat
l <- 1000
long_df <- data.table::data.table(id = sort(rep(1:l, 15)),
v1 = sort(rep(1:l, 15)),
imp = rep(1:15, l))
gads <- import_DF(long_df)
## check uniqueness
checkUniqueness2(gads, varName = "v1", idVar = "id", impVar = "imp")
#> [1] TRUE
