Simulated Data Based on Nominal Response IRT Model (Bock, 1972)


Data with 40 items is simulated based on the Nominal Response IRT Model (Bock, 1972). Each variable (column) represents an item and is a "character" variable. This is necessary to be able to run the CopyDetect2 function. The items are assumed to have five response alternatives: A, B, C, D, and E.

The item parameters used to generate data are taken from Wollack's study (1996).




A data frame with 500 hypothetical simulees.


Wollack, J.A.(1996). Detection of answer copying using item response theory. Dissertation Abstracts International, 57/05, 2015.

Bock (1972). Estimating item parameters and latent ability when responses are scored in two or more nominal categories. Psychometrika, 37, 29-51 .

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