ERIC Number: ED393881
Record Type: Non-Journal
Publication Date: 1995
Reference Count: N/A
Item Response Theory: Comparing BILOG and MicroCAT Calibration for a Mathematics Ability Test.
Carlson, Randal D.; Locklin, Ralph H.
This study reports the results of an investigation into the accuracy and efficacy of item calibration schemes used by two commercially available personal computer programs, BILOG and MicroCAT, when used to calibrate a test that is currently used in higher education. A calibration of 1,000 randomly selected students' responses to a 72-question math examination taken by all freshmen entering a large Eastern research university was performed using various available options of the two programs. A comparison was made between the calibration schemes concerning the parameters determined, item fits, and the resulting ability estimates. High agreement was found between the programs in item parameterization. BILOG appeared to provide a better fit to the chosen parameterization model in the 2- and 3-parameter cases. Estimation of abilities was also quite similar: differences encountered were more pronounced in the estimation of the ability of low scoring examinees. The effect of using a sample with all responses complete as contrasted with a sample containing omitted responses appeared to be quite small regardless of the program used. (Contains 4 tables, 6 figures, and 21 references.) (Author/SLD)
Publication Type: Reports - Research
Education Level: N/A
Authoring Institution: N/A