ERIC Number: ED190605
Record Type: Non-Journal
Publication Date: 1980-Apr
Reference Count: N/A
Comparison of Traditional and Latent Trait Theory Methods for Equating Tests.
Kolen, Michael J.
Results from equipercentile, linear, and latent trait equating of the vocabulary and quantitative thinking tests of the Iowa Tests of Educational Development were compared. The study entailed both the equating of forms (of similar difficulty) and the equating of levels (of differing difficulty). The goal was to equate seventh edition tests to those of the sixth edition. The data were item responses from a representative sample of 10,728 Iowa high school students. One-, two-, and three-parameter logistic latent trait methods were used. The results from the equating methods were compared using a cross-validation criterion which measured the closeness of converted score distributions to actual score distributions for randomly equivalent groups. The one-parameter methods results were judged inadequate for equating tests differing in difficulty, possibly because of prevalent examinee guessing. The three-parameter methods results were promising although two problems were discussed which require further study. Presently, equipercentile procedures may be the most viable for equating tests of differing difficulty. (Author/CP)
Publication Type: Speeches/Meeting Papers; Reports - Research
Education Level: N/A
Authoring Institution: N/A
Identifiers - Assessments and Surveys: Iowa Tests of Educational Development