This paper points out that there are certain generalizations about directions for guessing and methods of scoring that require that data be derived from random groups design. It supports the viewpoint that it is neither sufficient nor appropriate to make such generalizations on the basis of an analysis of scores obtained from the answer sheets of…

Birnbaum's three-parameter logistic item response model was used to study guessing behavior of low ability examinees on the Graduate Record Examinations (GRE) General Test, Verbal Measure. GRE scoring procedures had recently changed, from a scoring formula which corrected for guessing, to number-right scoring. The three-parameter theory was used…