lordif (version 0.1-2)

separate: splits item response vectors of DIF items by group

Description

Splits item response vectors of DIF items into separate group-specific vectors.

Usage

separate(resp, flag, gr)

Arguments

resp

a data frame (or matrix) of item response vectors

flag

a vector of DIF flags

gr

a vector of group identifiers

Value

• Returns a data frame with item response vectors for non-DIF items followed by separated item response vectors for DIF items

Details

To obtain group specific item calibrations, response vectors of DIF items are split into multiple vectors by group and treated as separate items.

See Also

lordif

Examples

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separate(resp,flag,gr)