Research Library

This investigation of Law School Admission Test (LSAT) preparation patterns for the 2014–2015, 2015–2016, 2016–2017, and 2017–2018 testing years represents a replication of earlier studies, with an additional testing year (i.e., the earlier studies spanned three administrations, whereas the present study spans four). From a list of nine possible test-preparation methods on the answer sheet, test takers were asked to voluntarily select the method(s) they had used to help them prepare for the test.

This investigation of Law School Admission Test (LSAT) preparation patterns for the 2011–2012, 2012–2013, and 2013–2014 testing years represents a replication of earlier studies. As with the earlier studies, all analyses in this report are descriptive in nature, and no attempt is made to evaluate the effectiveness of the various test-preparation methods.

Item response theory (IRT) is a mathematical model used to support the development, analysis, and scoring of tests and questionnaires. For example, IRT allows for the description of item (i.e., question) characteristics, such as difficulty, as well as the proficiency level of test takers. Various IRT models are available, and choosing the most appropriate model for a particular test is essential. Since the fit of the test data to the chosen model is never perfect, measuring the fit of the model to the data is imperative.

Item response theory (IRT) is a mathematical model that is often applied in the development and analysis of educational and psychological assessments. Various IRT models exist, and practitioners must choose the model that is most appropriate for their particular assessment. Even when the most appropriate model is applied, the fit of the assessment data to the model is rarely perfect in practice. How serious, then, is model misfit for practical decision-making?