In some testing programs an early item analysis is performed before final scoring in order to validate the intended keys. As a result, some items which are flawed and do not discriminate well may be keyed so as to give credit to examinees no matter which answer was chosen. This is referred to as allkeying. This research examined how varying the…

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…