psych (version 1.0-77)

make.keys: Create a keys matrix for use by score.items or cluster.cor

Description

When scoring items by forming composite scales either from the raw data using score.items or from the correlatio matrix using cluster.cor, it is necessary to create a keys matrix. This is just a short cut for doing so.

Usage

make.keys(nvars, keys.list, key.labels = NULL, item.labels = NULL)

Arguments

nvars

Number of variables items to be scored

keys.list

A list of the scoring keys,one element for each scale

key.labels

Labels for the scales can be specified here, or in the key.list

item.labels

Typically, just the colnames of the items data matrix.

Value

• keys
  a nvars x nkeys matrix of -1, 0, or 1s describing how to score each scale. nkeys is the length of the keys.list

Details

There are two ways to create keys for the score.items function. One is to laboriously do it in a spreadsheet and then copy them into R. The other is to just specify them by item number in a list.

See Also

score.items, cluster.cor, ~~~

Examples

data(attitude)
 key.list <- list(all=c(1,2,3,4,-5,6,7),
                  first=c(1,2,3),
                  last=c(4,5,6,7))
 keys <- make.keys(7,key.list,item.labels = colnames(attitude))
 keys
 
 scores <- score.items(keys,attitude,short=TRUE)
 scores
 
 data(bfi)
 keys.list <- list(agree=c(-1,2:5),conscientious=c(6:8,-9,-10),extraversion=c(-11,-12,13:15),neuroticism=c(16:20),openness = c(21,-22,23,24,-25))
 keys <- make.keys(25,keys.list,item.labels=colnames(bfi))
 scores <- score.items(keys,bfi,short=TRUE)
 scores