Stewart questioned Beglar's use of Rasch analysis of the Vocabulary Size Test (VST) and advocated the use of 3-parameter logistic item response theory (3PLIRT) on the basis that it models a non-zero lower asymptote for items, often called a "guessing" parameter. In support of this theory, Stewart presented fit statistics derived from…

A recent multidimensional scaling analysis of the Test of English-as-a-Foreign-Language (TOEFL) item response data identified clusters of items in the test sections that, being more homogeneous than their parent sections, might be better for diagnostic use. The analysis was repeated using different scoring techniques. Results diverged only for…

Five statistical indices are developed and described which may be used for determining (1) when linear equating of two approximately parallel tests is adequate, and (2) whan a more complex method such as equipercentile equating must be used. The indices were based on: (1) similarity of cumulative score distributions; (2) shape of the raw-score to…

A case study of the Florida Teacher Certification Examination (FTCE) program was described to assist others launching the development of large scale item banks. FTCE has four subtests: Mathematics, Reading, Writing, and Professional Education. Rasch calibrated item banks have been developed for all subtests except Writing. The methods used to…