Incomplete tests are handled differently for the P&P and CAT ASVAB versions. For the P&P-ASVAB, any unanswered items are treated as incorrect. For CAT-ASVAB examinees who do not complete the test before the time limit is exceeded, a penalty function is applied to their final ability estimate.
The penalty function has the following properties:
- The size of the penalty is related to the number of unfinished items.
- Examinees who answer the same number of items and have the same ability estimate receive the same penalty.
- The penalty eliminates the possibility of using “coachable” test-taking strategies to artificially increase test scores.
The final ability estimate computed using the penalty procedure is equivalent to the score that would be obtained if the examinee guessed at random on the unfinished items.
After the final ability estimate is computed, it is converted to a standard score on the ASVAB score scale that has been statistically linked to the ability estimate through a process called equating. Equating studies are conducted for every CAT-ASVAB item pool (and for every paper-and-pencil ASVAB form) to ensure that scores have the same meaning regardless of which item pool or test form the examinee receives.