collapse {lordif}R Documentation

collapses response categories

Description

collapses response categories if cell frequencies are less than the specified minimum threshold (i.e., minCell) and returns a vector of recoded values.

Usage

collapse(resp, group, minCell)

Arguments

resp a vector of item responses
group a vector of group designations
minCell a minimum cell frequency

Details

Collapses item response categories in resp if the two-way contingency table (resp x group) has cell frequencies less than the minimum cell count threshold specified by minCell.

Value

a numeric vector of the same length as resp with collapsed/recoded values.

Note

Item responses are expected to start from 1 not 0 (e.g., 1, 2, 3, 4, 5 and not 0, 1, 2, 3, 4). There must be at least two unique categories after collapsing/recoding.

Author(s)

Seung W. Choi <s-choi@northwestern.edu>

See Also

recode

Examples

  r1 <- c(1,1,2,1,1,2,2,1,2,2,1,2,2,1,1,2,1,2,2,3,3,1,2,3)
  gr <- c(0,0,0,1,1,0,1,1,0,0,1,0,1,1,0,1,0,1,0,1,0,1,0,1) 
  collapse(r1,gr,2) #minCell=2
  ## returns  c(1,1,2,1,1,2,2,1,2,2,1,2,2,1,1,2,1,2,2,2,2,1,2,2)
  ## response categories 2 and 3 are collapsed

[Package lordif version 0.1-4 Index]