rundif {lordif}R Documentation

runs ordinal logistic regression DIF

Description

Runs ordinal logistic regression DIF

Usage

  rundif(item, resp, theta, gr, criterion, alpha, beta.change, 
         pseudo.R2, R2.change)

Arguments

item a selection of items to be analyzed
resp a data frame containing item responses
theta a conditioning (matching) variable
gr a vector of group identifiers
criterion criterion for flagging (i.e., "CHISQR", "R2", or "BETA")
alpha significance level for Chi-squared criterion
beta.change proportional change for Beta criterion
pseudo.R2 pseudo R-squared measure (i.e., "McFadden", "Nagelkerke", or "CoxSnell")
R2.change R-squared change for pseudo R-squared criterion

Details

The argument item lists the column numbers of the data frame resp to be included in the analysis.

Value

Returns a list of the following components:

stats a data frame containing output statistics
flag a logical vector of DIF flags

Author(s)

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

References

Choi, S. W., Gibbons, L. E., & Crane, P. K. (under review). Development of an iterative hybrid ordinal logistic regression/IRT DIF: A Monte Carlo simulation approach for determining cutoff values. Behavior Research Methods.

Crane, P. K., Gibbons, L. E., Jolley, L., and van Belle, G. (2006). Differential item functioning analysis with ordinal logistic regression techniques: DIF detect and difwithpar. Medical Care, 44(11 Suppl 3), S115-S123.

See Also

runolr, lordif

Examples

##
## Not run: rundif(item,resp,theta,gr)

[Package lordif version 0.1-4 Index]