Abstract
We study academic integrity in a final exam of a compulsory course with 463 undergraduate students at a major Spanish university. The exam is an unproctored online multiple-choice exam without backtracking. A key characteristic is that for each type of problem, groups of students receive different versions. Since each version appears in both an earlier and later stage of the exam, we can exploit grade points and timestamps to study students' academic integrity. We observe a significant decrease in completion time in later rounds; however, surprisingly, there is no corresponding impact on average grade points. The precise number of different versions does not seem to have an effect on either variable. Our findings suggest that studies of potential cheating may have to pay attention to completion times apart from (or even instead of) grades.