Traditionally, women and minorities have not been fully represented in science and engineering. Numerous studies have attributed these differences to gaps in science achievement as measured by various standardized tests. Rather than describe mean group differences in science achievement across multiple cultures, this study focused on an in-depth…

There are at least two procedures to assess item difficulty stability in the Rasch model: robust z procedure and "0.3 Logit Difference" procedure. The robust z procedure is a variation of the z statistic that reduces dependency on outliers. The "0.3 Logit Difference" procedure is based on experiences in Rasch linking for tests developed by…

Indicator 8 of the State Performance Plan (SPP), developed under the 2004 reauthorization of the Individuals with Disabilities Education Act (IDEA 2004, Public Law 108-446) requires states to collect data and report findings related to schools' facilitation of parent involvement. The Schools' Efforts to Partner with Parents Scale (SEPPS) was…

The Revised Danish Learning Styles Inventory (R-D-LSI) (Nielsen 2005), which is an adaptation of Sternberg-Wagner Thinking Styles Inventory (Sternberg, 1997), comprises 14 subscales, each measuring a separate learning style. Of these 14 subscales, 9 are eight items long and 5 are seven items long. For self-assessment, self-scoring and…

Attempted to illuminate practical limitations on the Rasch model by focusing on the recovery of the density scale through five simulation trials. Results show that when error distributions are insufficient, the results may be ordinal at best, and when error distributions are nonsymmetrical, the positions of items may be biased with respect to the…

Examined the effectiveness of the Sympson-Hetter technique and rotated content balancing relative to no exposure control and no content rotation conditions in a computerized adaptive testing system based on the partial credit model. Simulation results show the Sympson-Hetter technique can be used with minimal impact on measurement precision,…

Describes a technique for obtaining item parameters of the Rasch model, a technique in which the item parameters are extracted from the eigenvectors of a matrix derived from comparisons between pairs of items. Describes advantages of this technique, which can be applied to both dichotomous and polytomous data. (SLD)

Studied the results provided by two strategies for fitting data to Latent Trait Theory models, Total-Persons-Items (TPI) and Total-Items-Persons (TIP). To assess these strategies, 30 items measuring religious attitudes were administered to 821 persons. Results show that TPI maximizes the number of persons with good fit, and TIP maximizes the…

Extended work in comparing item fit statistics and principal component analysis as tools for assessing the unidimensionality requirements of Rasch models and demonstrated methods to explore how violations of the unidimensionality requirement influence person measurement through 2 studies involving simulated rating scale data and responses to a…

Presents empirically based item selection guidelines for moving the cut score on equated tests consisting of "n" dichotomous items calibrated assuming the Rasch model. Derivations of lemmas that underlie the guidelines are provided as well as a simulated example. (SLD)

Studied item calibration stability in relation to response time and the levels of item difficulty between different response groups on a sample of 389 examinees responding to 6 subtest items of the Perceptual Ability Test of the Dental Admission Test. Results show that scores were equally useful for all groups, and different sources of item…

Describes an extension to the Rasch model for fundamental measurement in which there is parameterization not only for examinee ability and item difficulty but also for judge severity. Discusses variants of this model and judging plans, and explains its use in an empirical testing situation. (SLD)

Studied the effects of item grouping on local independence and item invariance, the characteristics of items scaled under the Rasch model that make them sample-free. Data were 107 responses to a survey of teachers' opinions about the Ontario grade 9 literacy test. Although effects of grouping and item phrasing on invariance were found, results…

Validated the Motivation Orientation scales of the Inventory of School Motivation (ISM) (M. Maher, 1984) across Navajo (n=760) and Anglo (n=1,012) students. Findings show that even though the ISM motivation orientation scales are applicable to students of different cultural backgrounds, meaningful cross-cultural comparisons should use the 30 items…

Applied the rating scale model (D. Andrich, 1978) to data from a survey of student satisfaction with college services using data from a single college with item samples sizes ranging from 2 to 355. Compared to items' average ratings, item parameter estimates in the rating scale model did a better job of predicting the item receiving the higher…