I don't know of any functions specifically designed to handle DIF (e.g., mantel-hantzel). But, ltm does give you the point estimates and standard errors so you can do a t-test between the focal and reference groups.
> -----Original Message----- > From: [EMAIL PROTECTED] > [mailto:[EMAIL PROTECTED] On Behalf Of SHEN,FENG > Sent: Tuesday, January 09, 2007 4:09 PM > To: r-help@stat.math.ethz.ch > Subject: [R] differential item function for item response theory > > Hi my friends, > > I'm very new to R and need your help. > > I used R and ltm package for item response theory (IRT) modeling. > I also need to compute differential item function (DIF) for > IRT models. I searched the archive but basically found nothing. > Could you help me find some sources about handling DIF of IRT? > > Many thanks in advance! > > Feng > > ______________________________________________ > R-help@stat.math.ethz.ch mailing list > https://stat.ethz.ch/mailman/listinfo/r-help > PLEASE do read the posting guide > http://www.R-project.org/posting-guide.html > and provide commented, minimal, self-contained, reproducible code. > ______________________________________________ R-help@stat.math.ethz.ch mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
