The GMAT2 is a generated dataset based on parameters from
Graduate Management Admission Test (GMAT, Kingston et al., 1985). First two items
were considered to function differently in uniform and non-uniform way respectively.
The dataset represents responses of 1,000 subjects to multiple-choice test of 20 items.
A correct answer is coded as 1 and incorrect answer as 0. The column group represents
group membership, where 0 indicates reference group and 1 indicates focal group.
Groups are the same size (i.e. 500 per group).
data(GMAT2)A GMAT2 data frame consists of 1,000 observations on the following 21 variables:
dichotomously scored items of the test
group membership vector, "0" reference group, "1" focal group
Kingston, N., Leary, L., & Wightman, L. (1985). An exploratory study of the applicability of item response theory methods to the Graduate Management Admission Test. ETS Research Report Series, 1985(2): 1--64.
Martinkova, P., Drabinova, A., Liaw, Y. L., Sanders, E. A., McFarland, J. L., & Price, R. M. (2017). Checking equity: Why differential item functioning analysis should be a routine part of developing conceptual assessments. CBE--Life Sciences Education, 16(2), rm2, 10.1187/cbe.16-10-0307.