Examining testlet effects in the TestDaF listening section: A testlet respons…

Testlets are subsets of test items that are based on the same stimulus and are administered together. Tests that contain testlets are in widespread use in language testing, but they also share a fundamental problem: Items within a testlet are locally dependent with possibly adverse consequences for test score interpretation and use. Building on testlet response theory (Wainer,Bradlow, & Wang, 2…