Despite the growing interest in incorporating response time data into item response models, there has been a lack of research investigating how the effect of speed on the probability of a correct response varies across different groups (e.g., experimental conditions) for various items (i.e., differential response time item analysis). Furthermore,…

Different indices can be used to measure an individual's pattern of responses on an achievement test as usual or consistent with the norm. The relationships among eight of these indices are investigated for a math and reading test given to approximately 2,100 fourth-grade students. (Author/BW)