We revisit the empirically observed positive correlation between DIF and difficulty studied by Freedle and commonly seen in tests of verbal proficiency when comparing populations of different mean latent proficiency levels. It is shown that a positive correlation between DIF and difficulty estimates is actually an expected result (absent any true…

The choice of anchor tests is crucial in applications of the nonequivalent groups with anchor test design of equating. Sinharay and Holland (2006, 2007) suggested "miditests," which are anchor tests that are content-representative and have the same mean item difficulty as the total test but have a smaller spread of item difficulties.…

Measures that accurately capture the phenomenon are critical to research and practice in group work. The vast majority of group-related measures were developed using the reflective measurement model rooted in classical test theory (CTT). Depending on the construct definition and the measure's purpose, the reflective model may not always be the…

Testing in educational system perform a number of functions, the results from a test can be used to make a number of decisions in education. It is therefore well accepted in the education literature that, testing is an important element of education. To effectively utilize the tests in educational policies and quality assurance its validity and…

Cronbach's coefficient alpha has been widely known and used in educational research. Many education research practitioners, however, may not be aware of the potential issues when the main assumptions for coefficient alpha are violated in research practice. This paper provides a brief discussion about two assumptions that may make the use and…

This paper describes an instrument designed for assessing learning outcomes in data management. In addition to assessment of student learning and ABET outcomes, we have also found the instrument to be effective for determining database placement of incoming information systems (IS) graduate students. Each of these three uses is discussed in this…

A directly applicable latent variable modeling procedure for classical item analysis is outlined. The method allows one to point and interval estimate item difficulty, item correlations, and item-total correlations for composites consisting of categorical items. The approach is readily employed in empirical research and as a by-product permits…

The purposes of an online system to auto-mark students' responses to mathematics test items are to expedite the marking process, to enhance consistency in marking and to alleviate teacher assessment workload. We propose that a semi-automatic marking and customizable feedback system better serves pedagogical objectives than a fully automatic one.…

This study aims to examine a) whether vocabulary knowledge, captured in the Vocabulary Levels Test (VLT), is related to the performance on the five types of reading comprehension items tested in TOEFL, i.e., Guessing Vocabulary, Main Idea, Inference, Reference, and Stated Detail; and b) whether EFL learners with different levels of vocabulary…

The traditional way of equating the scores on a new test form X to those on an old form Y is equipercentile equating for a population of examinees. Because the population is likely to change between the two administrations, a popular approach is to equate for a "synthetic population." The authors of the articles in this issue of the…

A variance-to-range ratio variable weighting procedure is proposed. We show how this weighting method is theoretically grounded in the inherent variability found in data exhibiting cluster structure. In addition, a variable selection procedure is proposed to operate in conjunction with the variable weighting technique. The performances of these…

A readily implemented procedure is discussed for interval estimation of indexes of interrelationship between items from multiple-component measuring instruments as well as between items and total composite scores. The method is applicable with categorical (ordinal) observed variables, and can be widely used in the process of scale construction,…

A conventional way to analyze item responses in multiple tests is to apply unidimensional item response models separately, one test at a time. This unidimensional approach, which ignores the correlations between latent traits, yields imprecise measures when tests are short. To resolve this problem, one can use multidimensional item response models…

The Organisation for Economic Cooperation and Development's (OECD's) Programme for International Student Assessment (PISA) surveys, which take place every three years, have been designed to collect information about 15-year-old students in participating countries. PISA examines how well students are prepared to meet the challenges of the future,…

This paper extends the theory of conditional covariances to polytomous items. It has been proven that under some mild conditions, commonly assumed in the analysis of response data, the conditional covariance of two items, dichotomously or polytomously scored, given an appropriately chosen composite is positive if, and only if, the two items…