checkLink: checkLink

In eatRest: eatRest

Description

Checks whether items in a dataset are linked via design. This may be useful in multiple matrix sampling designs.

Usage

checkLink ( dat, remove.non.responser = FALSE, na = NA, verbose = TRUE)

Arguments

dat	A data.frame where all columns denote test items
remove.non.responser	logical: Should cases with missings on all items be deleted?
na	character string specifying values to be treat as missing by design
verbose	logical: Should output printed to console?

Value

A logical value, i.e. TRUE or FALSE, indicating whether items in dataset are linked to each other.

Author(s)

Sebastian Weirich

Examples

dat    <- data.frame(item01 = c(1,0,NA,NA,NA), item02 = c(NA,NA,1,0,0), item03 = c(1,NA,NA,NA,NA) )
result <- checkLink(dat)
dat    <- data.frame(dat, item04 = c(0, NA,NA,NA,1) )
result <- checkLink(dat)

# checkLink for each dimension in science1
data(science1)
results <- by (data = science1.item.characteristics, INDICES = science1.item.characteristics$scale, FUN = function ( scales ) {
               collapsed <- collapseMissings(science1[,scales$item])
               results   <- checkLink(collapsed)
           })

# However, if only persons which anwered at least one item are considered
results <- by (data = science1.item.characteristics, INDICES = science1.item.characteristics$scale, FUN = function ( scales ) {
               collapsed <- collapseMissings(science1[,scales$item])
               results   <- checkLink(collapsed, remove.non.responser = TRUE)
           })

eatRest documentation built on May 2, 2019, 6:25 p.m.