It is a common practice for many standardized educational tests to employ a testlet-based format in which a bundle of items share a common stimulus (e.g., a reading passage or a situated task). According to Wainer and Kiely (1987), a testlet is an aggregation of items on a single theme. A common concern that arises regarding testlet-based tests is the violation of local independence (LID) assumption.
Resource Type
Research Report