This study represented a first attempt to evaluate the impact of local item dependence (LID) for Item Response Theory (IRT) scoring in computerized adaptive testing (CAT). The most basic CAT design and a simplified design for simulating CAT item pools with varying degrees of LID were applied. A data generation method that allows the LID among…

This report provides a description of the item types that have appeared on the Law School Admission Test (LSAT) from the first administration of the test in February 1948 through 1994. Also included is information related to the General Background and Writing tests that were administered for some time in an afternoon session, but for which…

Test takers were asked to report which, if any, methods they used to help prepare for the Law School Admission Test (LSAT). The study began with the 1991-1992 academic testing year and ended with the 1996-1997 academic testing year. More than 100,000 students responded in each of the years, with the exception of a smaller sample in 1996-1997…

Two-stage and multistage test designs provide a way of roughly adapting item difficulty to test taker ability. This study incorporated testlets (bundles of items) into two-stage and multistage designs, and compared the precision of the ability estimates derived from these designs with those derived from a standard computerized adaptive test (CAT)…

This study extended prior Law School Admission Council (LSAC) research related to the item response theory (IRT) local item independence assumption into the realm of classical test theory. Initially, results from the Law School Admission Test (LSAT) and two other tests were investigated to determine the approximate state of local item independence…

This study investigated the practical effects of local item dependence (LID) on item response theory (IRT) true-score equating. A scenario was defined that emulated the Law School Admission Test (LSAT) preequating model, and data were generated to assess the impact of different degrees of LID on final equating outcomes. An extreme amount of LID…

This study explored the impact of various degrees of violations of the item response theory (IRT) local independence assumption on the Law School Admission Test (LSAT) calibration and score distribution estimates. Initially, results from the LSAT and two other tests were investigated to determine the approximate state of local item dependence…

A model for constrained computerized adaptive testing is proposed in which the information on the test at the ability estimate is maximized subject to a large variety of possible constraints on the contents of the test. At each item-selection step, a full test is first assembled to have maximum information at the current ability estimate fixing…

This report describes trends related to accommodations in testing for the Law School Admission Test (LSAT) and summarizes the performance of accommodated LSAT takers for the 1993-1994 through 1997-1998 testing years. Data show that the number of requests for accommodated testing increased steadily from the 1994-1995 through 1996-1997 LSAT testing…