The current study research showed the nature and potential sources of gaps in mathematics achievement between English language learners (ELLs) non-English (non-ELLs). gap was examined using three DIF methodologies: including Mantel-Haenszel procedure, Rasch model, Hierarchical Generalized Linear Model (HGLM). These were conducted at item level contrast to total test level. Results revealed that...

The purpose of this study was to detect differentially functioning items in the University of Tehran English Proficiency Test (UTEPT) which is a high stake test of English developed and administered by the Language Testing Centre of the University of Tehran. This paper is based on the answers of 400 test takers to the test. All participants earned a master degree either in humanities or science...