Memory accessibility shapes explanation: Testing key claims of the inherence heuristic account

People understand the world by constructing explanations for what they observe. It is thus important to identify the cognitive processes underlying these judgments. According to a recent proposal, everyday explanations are often constructed heuristically: Because people need to generate explanations on a moment-by-moment basis, they cannot perform an exhaustive search through the space of possible reasons, but may instead use the information that is most easily accessible in memory (Cimpian & Salomon 2014a, b). In the present research, we tested two key claims of this proposal that have so far not been investigated. First, we tested whether—as previously hypothesized—the information about an entity that is most accessible in memory tends to consist of inherent or intrinsic facts about that entity, rather than extrinsic (contextual, historical, etc.) facts about it (Studies 1 and 2). Second, we tested the implications of this difference in the memory accessibility of inherent versus extrinsic facts for the process of generating explanations: Does the fact that inherent facts are more accessible than relevant extrinsic facts give rise to an inherence bias in the content of the explanations generated (Studies 3 and 4)? The findings supported the proposal that everyday explanations are generated in part via a heuristic process that relies on easily accessible—and often inherent—information from memory.     

An evaluation of the reliability of probability judgments across response modes and over time

Despite the importance of probability assessment methods in behavioral decision theory and decision analysis, little attention has been directed at evaluating their reliability and validity. In fact, no comprehensive study of reliability has been undertaken. Since reliability is a necessary condition for validity, this oversight is significant. The present study was motivated by that oversight. We investigated the reliability of probability measures derived from three response modes: numerical probabilities, pie diagrams, and odds. Unlike previous studies, the experiment was designed to distinguish systematic deviations in probability judgments, such as those due to experience or practice, from random deviations. It was found that subjects assessed probabilities reliably for all three assessment methods regardless of the reliability measures employed. However, a small but statistically significant decrease over time in the magnitudes of assessed probabilities was observed. This effect was linked to a decrease in subjects overconfidence during the course of the experiment.     

The affect heuristic in judgments of risks and benefits

This paper re‐examines the commonly observed inverse relationship between perceived risk and perceived benefit. We propose that this relationship occurs because people rely on affect when judging the risk and benefit of specific hazards. Evidence supporting this proposal is obtained in two experimental studies. Study 1 investigated the inverse relationship between risk and benefit judgments under a time‐pressure condition designed to limit the use of analytic thought and enhance the reliance on affect. As expected, the inverse relationship was strengthened when time pressure was introduced. Study 2 tested and confirmed the hypothesis that providing information designed to alter the favorability of one's overall affective evaluation of an item (say nuclear power) would systematically change the risk and benefit judgments for that item. Both studies suggest that people seem prone to using an ‘affect heuristic’ which improves judgmental efficiency by deriving both risk and benefit evaluations from a common source—affective reactions to the stimulus item. Copyright © 2000 John Wiley & Sons, Ltd.     

On the provenance of judgments of conditional probability

In standard treatments of probability, is defined as the ratio of to , provided that . This account of conditional probability suggests a psychological question, namely, whether estimates of arise in the mind via implicit calculation of . We tested this hypothesis (Experiment 1) by presenting brief visual scenes composed of forms, and collecting estimates of relevant probabilities. Direct estimates of conditional probability were not well predicted by . Direct estimates were also closer to the objective probabilities defined by the stimuli, compared to estimates computed from the foregoing ratio. The hypothesis that arises from the ratio fared better (Experiment 2). In a third experiment, the same hypotheses were evaluated in the context of subjective estimates of the chance of future events.     

People use the memory for past-test heuristic as an explicit cue for judgments of learning

When people estimate their memory for to-be-learned material over multiple study–test trials, they tend to base their judgments of learning (JOLs) on their test performance for those materials on the previous trial. Their use of this information—known as the memory for past-test (MPT) heuristic—is believed to be responsible for improvements in the relative accuracy (resolution) of people’s JOLs across learning trials. Although participants seem to use past-test information as a major basis for their JOLs, little is known about how learners translate this information into a judgment of learning. Toward this end, in two experiments, we examined whether participants factored past-test performance into their JOLs in either an explicit, theory-based way or an implicit way. To do so, we had one group of participants (learners) study paired associates, make JOLs, and take a test on two study–test trials. Other participants (observers) viewed learners’ protocols and made JOLs for the learners. Presumably, observers could only use theory-based information to make JOLs for the learners, which allowed us to estimate the contribution of explicit and implicit information to learners’ JOLs. Our analyses suggest that all participants factored simple past-test performance into their JOLs in an explicit, theory-based way but that this information made limited contributions to improvements in relative accuracy across trials. In contrast, learners also used other privileged, implicit information about their learning to inform their judgments (that observers had no access to) that allowed them to achieve further improvements in relative accuracy across trials.     

Aging and conditional probability judgments: a global matching approach

Age differences in bias in conditional probability judgments were investigated based on predictions derived from the Minerva-Decision Making model (M. R. P. Dougherty, C. F. Gettys, & E. E. Ogden, 1999), a global matching model of likelihood judgment. In this study, 248 younger and older adults completed frequency judgment and conditional probability judgment tasks. Age differences in the frequency judgment task are interpreted as an age-related deficit in memory encoding. Older adults' stronger biases in the probability judgment task point to age differences in criterion setting. Age-related biases were eliminated when age groups were equated on memory encoding by means of study time manipulation. The authors conclude that older adults' stronger judgment biases are a function of memory impairment.     

The memorizing effort heuristic in judgments of learning: A developmental perspective

Recent work on adult metacognition indicates that although metacognitive monitoring often guides control operations, sometimes it follows control operations and is based on the feedback from them. Consistent with this view, in self-paced learning, judgments of learning (JOLs) made at the end of each study trial decreased with the amount of time spent studying the item, suggesting that JOLs are based on the memorizing effort heuristic that easily learned items are more likely to be remembered. Study 1 extended investigation to primary school children. Whereas for third to sixth graders (9- to 12-year-olds) JOLs decreased with increasing study time (ST), no such relationship was found for first and second graders (7- and 8-year-olds). For both age groups, however, recall decreased with ST, supporting the validity of the memorizing effort heuristic. Self-reports (Study 2) disclosed the belief that recall should tend to increase with ST. The results bring to the fore the importance of mnemonic cues that shape metacognitive feelings even among primary school children. These cues lie in the very feedback that learners gain on-line from task performance rather than in metacognitive knowledge, and their use may also contribute to increased monitoring accuracy with age.     

Conditional probability judgments: Effects of imagining vs experiencing the conditioning event

Applications of Bayesian conditionalization often involve two temporal aspects: a probability judgment is based on knowledge at a point in time and is revised over time in light of added information. Let t, t′, and t″ designate three chronological points in time. E designates a target event which occurs or not at t″, and C designates a conditioning event which occurs or not at t′. Suppose that an individual judges P(EC) at t. If C occurs, Bayesian conditionalization requires that a judgment of P(E) at t′ is equal to the earlier judgment of P(EC). However, inconsistencies may result because a judgment of P(EC) at t is based on imagining C, while a judgment of P(E) at t′ is based on experiencing C. This study examines two sources of such inconsistencies. First, C normally is an abstraction of what might happen between t and t′. What actually happens may differ, such that an individual observes extraconditional information which affects a judgment of P(E) at t′. Second, experiencing C may change an individual's affective state, leading to greater optimism or pessimism about the occurrence of E. We report an experiment which documents both effects.     

Lottery judgments: A philosophical and experimental study

In this paper, we present the results of two surveys that investigate subjects’ judgments about what can be known or justifiably believed about lottery outcomes on the basis of statistical evidence, testimonial evidence, and “mixed” evidence, while considering possible anchoring and priming effects. We discuss these results in light of seven distinct hypotheses that capture various claims made by philosophers about lay people’s lottery judgments. We conclude by summarizing the main findings, pointing to future research, and comparing our findings to recent studies by Turri and Friedman.     

Heading judgments in minimal environments: the value of a heuristic when invariants are rare

Observers made systematic heading judgments in two experiments simulating their translation through an environment with only two trees. When those trees converged or decelerated apart, observers tended to follow the invariant information and make heading judgments outside the near member of the pair. When those trees accelerated apart, however, observers tended to follow the heuristic information and make judgments outside the far member, although this result was tempered by the angular separation between the trees and their relative acceleration. The simultaneous existence and use of invariants and heuristics are discussed in terms of different metatheoretical approaches to perception.     

Understanding conjunction effects in probability judgments: the role of implicit mental models

Subjective probability judgments often violate a normative principle in that the conjunction of two events is judged to be more likely than the probability of either of the two events occurring separately. Most previous explanations of these conjunction effects have assumed that probability judgments depend on some psychological relation (e.g. representativeness) between the constituents mentioned explicitly in the stimulus information. In contrast, the present approach highlights the fundamental role of implicitly inferred information. Participants are assumed to transform the explicit stimulus information into implicit mental models in their attempt to make sense of the experimental task. Probability judgments should then reflect the degree of activation of such a mental model in memory given a set of propositions, rather than the quantitative fit or likelihood of the propositions themselves. Two studies are reported which provide converging evidence for the proposed mental model approach. In the first study, using graded conjunctions of one to five propositions, probability judgments are shown to vary as a function of the activation of a mental model rather than the likelihood of the component events. In a second study, a priming procedure is employed to activate mental models that either fit an event conjunction or do not, leading to an increase or decrease of conjunction effects in probability judgment. Copyright © 1999 John Wiley & Sons, Ltd.     

The effect of imagining an event on expectations for the event: An interpretation in terms of the availability heuristic

Previous studies have indicated that explaining a hypothetical event makes the event seem more likely through the creation of causal connections. However, such effects could arise through the use of the availability heuristic; that is, subjective likelihood is increased by an event becoming easier to imagine. Two experiments were designed to demonstrate this principle. In Experiment 1, subjects asked to imagine Jimmy Carter winning the presidential election (prior to the election) predicted that he was more likely to win than subjects asked to imagine Gerald Ford winning. In Experiment 2, subjects asked to imagine a good college football season for the previous championship team were more likely to predict a major bowl bid than subjects asked to imagine a bad season, although the effect did not appear in predictions of the season record. In both studies, subjects who were also asked to explain the imaginary event were no different from subjects who only imagined. Several other attributional distortions are interpreted in terms of the availability heuristic.     

Dilution and confirmation of probability judgments based on nondiagnostic evidence

Previous research has shown that probability judgments based on a mix of diagnostic and nondiagnostic information are less extreme than judgments based on the diagnostic information alone. Results of the present experiments suggest that this dilution effect holds only under a limited set of conditions. When judgments based on a mix of diagnostic and nondiagnostic information are compared with separately elicited judgments based on the diagnostic information alone, the dilution effect is consistently observed. When judgments based on the diagnostic evidence are revised in light of additional, nondiagnostic evidence, by contrast, the dilution effect is eliminated or even reversed (yielding a confirmation effect) depending on the type of nondiagnostic evidence under evaluation.     

The ease-of-processing heuristic and the stability bias: dissociating memory, memory beliefs, and memory judgments

Judgments about memory are essential in promoting knowledge; they help identify trustworthy memories and predict what information will be retained in the future. In the three experiments reported here, we investigated the mechanisms underlying predictions about memory. In Experiments 1 and 2, single words were presented once or multiple times, in large or small type. There was a double dissociation between actual memory and predicted memory: Type size affected predicted but not actual memory, and future study opportunities affected actual memory but scarcely affected predicted memory. The results of Experiment 3 suggest that beliefs and judgments are largely independent, and neither consistently resembles actual memory. Participants' underestimation of future learning-a stability bias-stemmed from an overreliance on their current memory state in making predictions about future memory states. The overreliance on type size highlights the fundamental importance of the ease-of-processing heuristic: Information that is easy to process is judged to have been learned well.     

Comparing two perceived characteristics of autobiographical memory: Memory detail and accessibility

Four samples of participants recalled autobiographical memories. While some evidence emerged from regression analyses suggesting that judgements of the amount of detail contained in each memory and judgements of the ease with which events could be recalled were partially independent, the analyses generally showed that these judgements were similarly predicted by various event characteristics (age, typicality, self-importance, emotional intensity at event occurrence, rehearsal types). Co-occurrence frequency data yielded similar conclusions, showing that while ease ratings and detail ratings occasionally diverged, they were more often consistent with each other. Finally, the data also suggested that events that prompted emotional ambivalence were not judged to be more easily recalled, or to contain more detail, than non-ambivalent events.     

Comparing two perceived characteristics of autobiographical memory: Memory detail and accessibility

Four samples of participants recalled autobiographical memories. While some evidence emerged from regression analyses suggesting that judgements of the amount of detail contained in each memory and judgements of the ease with which events could be recalled were partially independent, the analyses generally showed that these judgements were similarly predicted by various event characteristics (age, typicality, self-importance, emotional intensity at event occurrence, rehearsal types). Co-occurrence frequency data yielded similar conclusions, showing that while ease ratings and detail ratings occasionally diverged, they were more often consistent with each other. Finally, the data also suggested that events that prompted emotional ambivalence were not judged to be more easily recalled, or to contain more detail, than non-ambivalent events.     

The impact of perceived experience on likelihood judgments for self and others: an experimental approach

This study examines the effect of an experimental manipulation of perceived experience on self and others' likelihood ratings for a set of relatively commonplace misfortunes. Participants were randomly assigned to a condition in which they were asked whether they had ever experienced the events (designed to induce higher perceived experience) or whether they had done so frequently, typically, etc. (designed to induce lower perceived experience). The manipulation led to increases in ratings of both perceived self‐likelihood and others' likelihood, in ease of imagining the outcome and recall of a past occurrence, and to decreases in perceived control over the events in the higher perceived experience condition. The increases in ease of imagining mediated the impact of manipulated experience on comparative likelihood whereas the decreases in perceived control did not. There was little evidence that event controllability moderated the impact of experience on comparative likelihood for these events. Copyright © 2006 John Wiley & Sons, Ltd.     

Aging and working memory inside and outside the focus of attention: dissociations of availability and accessibility

Two experiments used the N-Back task to test for age differences in working memory inside and outside the focus of attention. Manipulations of the difficulty of item-context binding (Experiment 1) and of stimulus feature binding (Experiment 2) were used to create conditions that varied in their demand on working memory, with the expectation that greater demand might increase age differences in focus-switching costs and the search rate outside the focus of attention. Results showed, however, that although age differences were evident in measures of overall speed and accuracy, and the manipulations significantly affected response times and accuracy in the expected direction, the experimental manipulations had no impact on age differences. Findings instead pointed to age-related reductions in accuracy but not speed of focus-switching and search outside the focus of attention. Thus, age-related deficits appear to involve the availability of representations in working memory, but not their accessibility.     

The informational basis of social judgments: Memory for informative and uninformative arguments

This study investigates the encoding and retrieval of arguments in an opinion formation task. It is based on a model of opinion formation that partitions the latter process into initial encoding, elaborative encoding, integration, and decision. According to this model elaborative encoding depends on two factors: (i) the informativeness of the arguments and (ii) their thematic relatedness. Since it is reasonably well established that the likelihood of retrieving an argument is an increasing function of the amount of elaboration performed on it, the first hypothesis is straightforward, namely, that the memory for an argument will increase with its informativeness and with its thematic relatedness to other arguments. The second hypothesis assumes that by dint of their closer association with the decision, informative arguments occupy a more central position in the representation of an opinion than uninformative ones. This implies that an informative argument should be accessed and reported prior to an uninformative argument, even when differences in retrievability (i.e., probabilities of recall) are controlled. The findings were consistent with such an analysis.