Effects of Item-Selection Criteria on Classification Testing with the Sequential Probability Ratio Test

This paper presents comparisons among three item-selection criteria for the sequential probability ratio test. The criteria were compared in terms of their efficiency in selecting items, as indicated by average test length (ATL) and the percentage of correct decisions (PCD). The item-selection criteria applied in this study were the Fisher information function, the KullbackLeibler information function, and a weighted log-odds ratio. We also examined the effects of the cutoff scores, the width of the indifference region, the item pool size, and the item exposure rate under the different item-selection criteria. The results of the computer simulations showed that the three criteria yielded very small differences in the outcome measures, regardless of the conditions imposed.