Graduation Year


Document Type




Degree Name

Doctor of Education (Ed.D.)

Degree Granting Department

Educational Measurement and Research

Major Professor

Eun Sook Kim, Ph.D.

Committee Member

John Ferron, Ph.D.

Committee Member

Jeffrey Kromrey, Ph.D.

Committee Member

Kristine Hogarty, Ph.D.


DIF, Dfferential Item Functioning, PROC IRT, Rasch


The purpose of this study was to determine if using a multistage approach for the empirical selection of anchor items would lead to more accurate DIF detection rates than the anchor selection methods proposed by Kopf, Zeileis, & Strobl (2015b). A simulation study was conducted in which the sample size, percentage of DIF, and balance of DIF were manipulated. The outcomes of interest were true positive rates, false positive rates, familywise false positive rates, anchor contamination rates, and familywise anchor contamination rates. Results showed the proposed multistage methods produced lower anchor contamination rates than the non-multistage methods under some conditions, but there were generally no meaningful differences in true positive and false positive rates.