This study investigated to what extent, and under what circumstances, pair collaboration influences the realism in eyewitness confidence in event memory. The participants first saw a short film clip and then confidence rated their answers to questions on its content. A condition (the Individual–Pair condition) where individual effort preceded pair collaboration showed better calibration compared with a condition (the Simple Pair condition) where no individual effort took place. Furthermore, within the Individual–Pair condition, better calibration, and lower overconfidence, were found in the pair phase compared with the individual phase. The eyewitnesses in the Individual–Pair condition made more realistic judgements of the total number of questions answered correctly. In a control experiment no effect on realism in confidence was found when individuals performed the same task twice. The improved realism in the Individual–Pair condition may partly be explained in terms of the increased accuracy and lowered confidence found for such items where the pair members’ had given different answers in the individual phase, and by a risky shift effect for such items where they had given the same answer.

The aim of the study was to investigate the relation between the phenomenological quality of memory (Tulving, 1985) and the realism (validity) in confidence judgement when using emotional pictures (I.A.P.S; Lang, Ohman, & Vaitl, 1988). A series of three experiments was completed where the participants judged the phenomenological quality of their memory and/or their confidence. The results showed facilitation for the negative pictures in a matrix search task in the encoding phase, where negative pictures were more easily and quickly detected, compared to positive ones. In the memory phase of the experiments a higher degree of recollective experience (a larger proportion of 'remember' responses) was found for negative pictures. A higher level of confidence for recognition of negative pictures than for positive ones was obtained, but no general valence dependent effect on the realism in the confidence judgement was found. However, when analysing only the remember responses, negative pictures showed higher overconfidence than the positive pictures. The results support that a recollective experience induces higher confidence and overconfidence. 

The present study investigated differences in judgments of one’s own and others’ knowledge (the own-other difference). Consistent with the below-average effect (e.g., Kruger, 1999), our main results showed that the participants gave lower knowledge ratings of their own extent of knowledge than of another person’s extent of knowledge (Experiment 1). Furthermore, lower and more realistic judgments were found when the participants judged their own as compared with when judging another person’s overall accuracy (frequency judgments) of answering knowledge questions correctly (Experiment 1 and 2). On the basis of these results it is argued that judgmental anchoring may be important also in the context of indirect comparisons, and that previous conclusions of cross-cultural psychology regarding the above-average effect may be oversimplified.

Witnesses’ event recall and the realism in their evaluation of the correctness of their recall are of great importance in forensic processes. These issues were investigated in the present study by use of calibration methodology. More specifically, we analyzed the effects of two recalls of the same event (repetition) and of probes (non-informative follow-up questions at recall) on 9–11 year-old children’s and adults’ open free recall and the degree of realism in the participants’ confidence judgments of the correctness of the recall after they had seen a short video clip. The findings were that repetition resulted in more units recalled both for children and for adults, and in that the children showed higher overconfidence compared with one recall, but not the adults. Moreover, when only the statements in the repetition conditions that were recalled twice were included in the analysis, higher confidence was found for the children (independent of an increase in the proportion correct statements of all statements) but not for the adults. Probing increased the number of units recalled for both children and adults, decreased the children’s proportion correct statements but not the adults’, decreased both children’s and adults’ confidence and increased the children’s overconfidence, but not the adults’. Finally, the combination of two recalls and probing disrupted the children’s but not the adults’ metacognitive performance.

We present the generalized signal detection theory (GSDT), where familiarity is described by a sparse binomial distribution of binary node activity rather than by normal distribution of familiarity. Items are presented in a distributed representation, where each node receives either noise only, or signal and noise. An old response (i.e., a "yes" response) is made if at least one node receives signal plus noise that is larger than the activation threshold, and item variability is determined by the distribution of activated nodes as the threshold is varied. A distinct representation leads to better performance and a lower ratio of new to old item variability, than a more distributed and less distinct representations. Here we apply the GSDT to empirical data on verbal and olfactory memory and suggest that verbal memory relies on a distinct neural item representation, whereas olfactory memory has a fuzzy neural representation leading to poorer memory and inducing a larger ratio of new to old item variability.