In 1990 a routine study confirming the accuracy of the Rasch model in predicting item difficulties led to an in-depth analysis of the impact of guessing on the Rasch model when used with multiple-choice items. This paper reviews the highlights of that research. Seventeen linked vocabulary tests of 110 items were each administered to groups of 400…

A 1992 study by R. Gershon found discrepancies when comparing the theoretical Rasch item characteristic curve with the average empirical curve for 1,304 vocabulary items administered to 7,711 students. When person-item mismatches were deleted (for any person-item interaction where the ability of the person was much higher or much lower than the…

This paper describes the use of the Rasch model to help implement computerized administration of the standard and advanced forms of Raven's Progressive Matrices (RPM), to compare relative item difficulties, and to convert scores between the standard and advanced forms. The sample consisted of 95 girls and 95 boys in Australia. (SLD)

The psychometric characteristics of constructed response items referring to choice and nonchoice passages administered to approximately 150,000 students in grades 3, 5, and 8 were studied through item response theory methodology. Results indicated no consistent differences in the difficulty and discrimination of items referring to the two types of…

Item components that might contribute to the difficulty of items on the Raven Colored Progressive Matrices (CPM) and the Standard Progressive Matrices (SPM) were studied. Subjects providing responses to CPM items were 269 children aged 2 years 9 months to 11 years 8 months, most of whom were referred for testing as potentially gifted. A second…

Describes the use of Rasch item statistics for curricular analysis and instructional decision making. Uses a case study of application of the Rasch model in the pilot testing of items selected for criterion-referenced tests developed for grades one through eight in Charleston (South Carolina) schools. (SLD)