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Most high-stakes testing programs apply methods to identify unlikely patterns of correct/incorrect responses to test questions. Some examples of why such patterns may occur include misinterpretation of questions, question preknowledge, answer copying, or guessing behavior. This report provides an overview of existing approaches to identifying atypical response patterns that fall into a class of analyses known as nonparametric statistics. Results of a simulation study comparing the different approaches, along with guidelines for applying these indices in practice, are also presented.

Automated methods have been developed for assembling test forms, evaluating a pool of test questions (i.e., items) to determine the number of test form assemblies it can support, and designing an item pool that can most efficiently support the test form assembly process. Automated methods have greatly maintained and improved such activities, all of which are essential to the support of every testing program. This report reviews the major approaches that have been applied in the development of these methods.

The problems of item pool analysis and design are the subject of many recent studies. The rationale for this type of research is to increase the usability of existing item pools and to decrease the cost of designing new items. Clearly these are crucial problems for all testing agencies.

Many standardized tests are now administered via computer rather than paper-and-pencil format. The computer-based delivery mode brings with it certain advantages, one of which is the ability to record not only the test taker’s response to each item (i.e., question), but also the amount of time the test taker spends considering and answering each item. Research on how to represent and utilize response time data has proliferated, but most of the research is based on the assumption of constant working speed in relation to a certain accuracy level.

Since the inception of the Law School Admission Test (LSAT), the Law School Admission Council (¾«¶«Ó°Òµ) has sought to evaluate and ensure its validity for use in the law school admission process. As predictive validity is an important component in the overall evaluation of test validity, ¾«¶«Ó°Òµ has carried out annual predictive validity studies, also called LSAT Correlation Studies, since the test was first administered.

Test theory typically deals with categorical responses to test questions (items), for instance, correct/incorrect responses or responses that represent a choice from a finite number of alternatives. Whenever technically possible, it is attractive to collect information on continuous response variables that accompany these responses as a covariate. One obvious example is response time; other examples are information on cursor movement in computer-based testing, eye-tracking information, or physiological information.

Many standardized tests are now administered via computer rather than paper and pencil. The computer-based delivery mode brings with it certain advantages, such as the ability to record not only the test taker’s response to each item (i.e., question), but also the amount of time the test taker spends considering and answering each item. The analysis of response times (RTs) is still a developing area of research.

This project examined the relevance of law school alumni networks to graduates’ careers. Two studies investigated intraorganizational and interorganizational influences on graduates’ careers; an ongoing third study investigates how these influences vary by gender, race/ethnicity, and school attended.

In high-stakes testing, it is important to verify the validity of individual test scores. Although a test, in general, results in valid test scores for most test takers, there may be individual test takers with unusual answer patterns for whom test score validity is questionable. One example of such aberrance is a test taker who guesses on a large number of questions or one who has preknowledge of the answers to some questions. An effective statistical technique (developed for a single test) was extended for tests that consist of multiple subtests, as does the Law School Admission Test.

Several statistics used to detect inconsistent patterns of correct/incorrect answers to test questions (items) were evaluated based on data from one Analytical Reasoning (AR) and one Logical Reasoning (LR) section of the Law School Admission Test. Item score patterns were also evaluated based on gender and racial/ethnic subgroups. We showed that test takers who were consistently flagged by all statistics evaluated and for both the AR and the LR sections had relatively low scores, which may have been the result of extensive guessing.

With computerized testing, it is possible to record both the responses of test takers to test questions (i.e., items) and the amount of time spent by a test taker in responding to each question. Various models have been proposed that take into account both test-taker ability and working speed, with many models assuming a constant working speed throughout the test. The constant working speed assumption may be inappropriate for various reasons.

A mathematical model called item response theory is often applied to high-stakes tests to estimate test-taker ability level and to determine the characteristics of test questions (i.e., items). Often, these tests contain subsets of items (testlets) grouped around a common stimulus. This grouping often leads to items within one testlet being more strongly correlated among themselves than among items from other testlets, which can result in moderate to strong testlet effects.

Text similarity measurement provides a rich source of information and is increasingly being used in the development of new educational and psychological applications. However, due to the high-stakes nature of educational and psychological testing, it is imperative that a text similarity measure be stable (or robust) to avoid uncertainty in the data. The present research was sparked by this requirement. First, multiple sources of uncertainty that may affect the computation of semantic similarity between two texts are enumerated.

This report presents a new algorithm for detecting groups of test takers (aberrant groups) who had access to subsets of test questions (aberrant subsets) prior to an exam. This method is in line with the development of statistical methods for detecting test collusion, a new research direction in test security. Test collusion may be described as the large-scale sharing of test materials, including answers to test questions. The algorithm employs several new statistics to perform a sequence of statistical tests to identify aberrant groups.

The Law School Admission Council (¾«¶«Ó°Òµ) has carried out annual predictive validity studies, also called LSAT Correlation Studies, since the Law School Admission Test (LSAT) was first administered. These studies are geared toward evaluating and ensuring the effectiveness and validity of LSAT scores for use in the law school admission process. In conjunction with these predictive validity studies, ¾«¶«Ó°Òµ also conducts differential validity and differential prediction studies on the LSAT to ensure that the test is fair across gender subgroups.

The Law School Admission Council (¾«¶«Ó°Òµ) has carried out annual predictive validity studies, also called LSAT Correlation Studies, since the Law School Admission Test (LSAT) was first administered. These studies are geared toward evaluating and ensuring the effectiveness and validity of LSAT scores for use in the law school admission process. In conjunction with these predictive validity studies, ¾«¶«Ó°Òµ also conducts differential validity and differential prediction studies on the LSAT to ensure that the test is fair across racial/ethnic subgroups.

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.

Many standardized tests are now administered via computer rather than paper-and-pencil format. In a computer-based testing environment, it is possible to record not only the test taker’s response to each question (item), but also the amount of time spent by the test taker in considering and answering each item. Response times (RTs) provide information not only about the test taker’s ability and response behavior but also about item and test characteristics. The current study focuses on the use of RTs to detect aberrant test-taker responses.

Although law schools have seen rising representation of diverse racial/ethnic groups among students, minorities continue to represent disproportionately small percentages of lawyers within large corporate law firms. Prior research on the nature and causes of minority underrepresentation in such firms has been sparse. In this research project, we examined variation across large U.S.