Confucius pointed out that the first step toward wisdom is calling things by the right name. The term "Differential Item Functioning" (DIF) did not arise fully formed from the miasma of psychometrics, it evolved from a variety of less accurate terms. Among its forebears was "item bias" but that term has a pejorative connotation…

In 2008, Penfield showed that measurement invariance across all response options of a multiple-choice item (correct option and the "J" distractors) can be modeled using a nominal response model that included a differential distractor functioning (DDF) effect for each of the "J" distractors. This article extends this concept to consider how the…

We are living in a conceptual world which we build through both informal and systematic interaction. Concepts enable us to simplify and organize our environment and communicate efficiently with others. The learning of concepts is represented by a general idea, usually expressed by a word, which represent a class or group of things or actions…

Six Practice Tests for the iBT gives students plenty of practice as they prepare for the Internet-based TOEFL (iBT) or the new form of the institutional TOEFL (ITP). This new book/audio set contains a concise description of the TOEFL and the types of questions in each section, as well as six full-length tests that have not been published before.…

Robust screening measures that perform well in different populations could help improve the accuracy of diagnosis of pediatric bipolar disorder. Changes in sampling could influence the performance of items and potentially influence total scores enough to alter the predictive utility of scores. Additionally, creating a brief version of a measure by…

In the presence of test speededness, the parameter estimates of item response theory models can be poorly estimated due to conditional dependencies among items, particularly for end-of-test items (i.e., speeded items). This article conducted a systematic comparison of five-item calibration procedures--a two-parameter logistic (2PL) model, a…

Successful administration of computerized adaptive testing (CAT) programs in educational settings requires that test security and item exposure control issues be taken seriously. Developing an item selection algorithm that strikes the right balance between test precision and level of item pool utilization is the key to successful implementation…

Many students with learning disabilities (SLD) participate in standardized assessments using test accommodations such as extended time, having the test items read aloud, or taking the test in a separate setting. Yet there are also aspects of the test items themselves, particularly the language demand, which may contribute to the effects of test…

The language of mathematics is unique and complex. One feature of the mathematical register is the use of symbols and abbreviations. Whilst it may be possible for a student to think mathematically in the absence of symbols, the written communication of mathematical ideas cannot be achieved concisely without the use of mathematical symbols.…

This study examined whether the number of options in the Likert scale influences the psychological distance between categories. The most important assumption when using the Likert scale is that the psychological distance between options is equal. The authors proposed a new algorithm for calculating the scale values of options by applying item…

The traditional approach to scale modified-Angoff cut scores transfers the raw cuts to an existing raw-to-scale score conversion table. Under the traditional approach, cut scores and conversion table raw scores are not only seen as interchangeable but also as originating from a common scaling process. In this article, we propose an alternative…

The analysis of differential item functioning (DIF) examines whether item responses differ according to characteristics such as language and ethnicity, when people with matching ability levels respond differently to the items. This analysis can be performed by calculating various statistics, one of the most important being the Mantel-Haenszel,…

This article demonstrates how textbooks differ in their description of the term "experimental unit". Advanced Placement Statistics teachers and students are often limited in their statistical knowledge by the information presented in their classroom textbook. Definitions and descriptions differ among textbooks as well as among different…

General chemistry tests from the Examinations Institute of the Division of Chemical Education of the American Chemical Society have been analyzed to identify factors that may influence how individual test items perform. In this paper, issues of item order (position within a set of items that comprise a test) and answer order (position of correct…

Rosner and Kochanski (2009) noticed an inconsistency in the mathematical statement of the Law of Categorical Judgment and derived "the valid equation, the Law of Categorical Judgment (Corrected)" (p. 125). The purpose of this comment is to point out that the law can be corrected in many different ways, leading to substantially different…