Simulated data were used to investigate systematically the impact of various characteristics of the threshold values (number, symmetry, and distance between adjacent threshold values) and of the delta values on the distribution of item information in the successive intervals Rasch model. The results revealed that the shift in the peak of the information function away from the scale value of an item depended on the degree of asymmetry of the threshold values and the magnitude of the delta value of the item. The implications of the findings for computerized adaptive attitude measurement are discussed.
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