Separation of encoding fluency and item difficulty effects on judgements of learning

Abstract

The fluency of information encoding has frequently been discussed as a major determinant of predicted memory performance indicated by judgements of learning (JOLs). Previous studies established encoding fluency effects on JOLs. However, it is largely unknown whether fluency takes effect above and beyond the effects of item difficulty. We therefore tested whether encoding fluency still affects JOLs when numerous additional cues indicating the difficulty of an item are available as well. In three experiments, participants made JOLs for another participant while observing his or her self-paced study phase. However, study times were swapped in one experimental condition, so that items with short study times (indicating high fluency) were presented for long durations, whereas items with long study times (indicating low fluency) were presented for short durations. Results showed that both item difficulty and encoding fluency affected JOLs. Thus, encoding fluency in itself is indeed an important cue for JOLs that does not become redundant when difficulty information is available in addition. This observation lends considerable support to the ease-of-processing hypothesis.

Keywords:

• Judgements of learning
• Encoding fluency
• Ease of processing
• Metacognitive heuristics
• Metamemory

Experiment 1 is based in part on Monika Undorf's doctoral thesis.

Notes

¹ We stick to a narrow definition proposed by Dunlosky and Metcalfe (2008), according to which the ease-of-processing hypothesis encompasses the influence of encoding fluency on JOLs exclusively. The ease-of-processing hypothesis more broadly defined (e.g., Kornell, Rhodes, Castel, & Tauber, 2011) also includes influences of retrieval fluency and perceptual fluency on JOLs (for a discussion of different aspects of processing fluency, see Undorf & Erdfelder, 2011).

² Analyses of gamma correlations between cued recall performance and both study time and JOLs included data from 39 participants in the original study time condition only. Data from one participant had to be excluded from these analyses, because he or she correctly recalled all items, so that neither the study time–cued recall correlation nor the JOL–cued recall correlation was defined for this participant.

³ The pattern of results is identical, however, when all items are included in the analyses. The same is true for Experiment 2 and Experiment 3.

⁴ Analyses of gamma correlations between cued recall performance and both study time and JOLs included data from 47 participants in the swapped study time condition only, because one participant correctly recalled all items.