The role of memory for past test in the underconfidence with practice effect

According to the Memory for Past Test (MPT) heuristic, judgments of learning (JOLs) may be based, in part, on memory for the correctness of answers on a previous test. The authors explored MPT as the source of the underconfidence with practice effect (UWP; A. Koriat, L. Sheffer, & H. Ma'ayan, 2002), whereby Trial 1 overconfidence switches to underconfidence by Trial 2. Immediate and delayed JOLs were contrasted because only immediate JOLs demonstrate UWP. Consistent with MPT for immediate JOLs, Trial 1 test performance better predicted Trial 2 JOLs than did Trial 2 test performance. Delayed JOLs showed the reverse. Furthermore, items forgotten on Trial 1 but remembered on Trial 2 contributed disproportionately to UWP, but only with immediate JOLs.