Multiple study trials and judgments of learning.

We compared judgments of learning (JOLs) that were made either (a) after 1 study trial, (b) 2 study trials, or (c) in-between the 1st and 2nd study trials. In regard to the absolute accuracy of JOLs at predicting subsequent recall, we replicated previous findings of an underconfidence-with-practice effect for immediate JOLs and report for the first time a new finding of an underconfidence-with-practice effect for delayed JOLs (i.e., delayed JOLs after one trial overestimated the likelihood of subsequent recall, whereas delayed JOLs after two trials underestimated that likelihood). Also, although delayed JOLs always had a greater relative accuracy than did immediate JOLs, the relative accuracy of immediate and delayed JOLs was approximately the same after 1 versus 2 study trials. These results demonstrate that additional study trials affect the absolute accuracy of all JOLs but not the relative accuracy of any JOLs. Thus an increase in the number of study trials produced an increasing bias to be underconfident about the subsequent likelihood of recall but did not affect people's ordering of which items had been more (versus less) well-learned.