Confidence judgments in studies of individual differences

This paper examines psychometric properties of scores derived from calibration curves (overconfidence, calibration, resolution, and slope) and an analogue of overconfidence that is based on a posttest estimate of the proportion of correctly solved items. Four tests from the theory of fluid and crystallized intelligence were used, and two of these tests employed both sequential and simultaneous methods of item presentation. The results indicate that the overconfidence score not only has the highest reliability, but is the only score with a reliability normally considered adequate for use in individual differences research. There is some, albeit weak, difference in subjects' level of overconfidence between sequential and simultaneous methods of item presentation. Correlational evidence confirms our previous findings that overconfidence scores from perceptual and ‘knowledge’ tasks define the same factor. In agreement with the results of Gigerenzer, Hoffrage and Kleinbolting (1991), subjects' post-test estimates of their performance showed lower levels of overconfidence than did the traditional measures based on subjects' confidence judgment responses to individual items. Also, after controlling for the actual test performances, the post-test performance estimates and average confidence ratings were only slightly positively correlated, suggesting that different psychological processes may underlie these two measures. Finally, our results suggest that average confidence over all items in the test may be a more useful measure in individual differences research than scores derived from calibration curves.     

A choice theory analysis of similarity judgments

The selection of one of several stimuli as most similar to a reference stimulus is assumed to satisfy a choice axiom that permits assigning ratio scale values to each variable-reference stimuli pair. The logarithm of this scale is treated as a distance measure, leading to the following testable conclusions about the pairwise choice probabilities as the reference stimulus is varied. First, the plot is a symmetrically truncated ogive with horizontal tails. Second, if two pairs of choice stimuli have the same midpoint, the ogive of one pair is part of the ogive of the other. In terms of this model, the hysteresis and midpoint displacement effects in the method of bisection are discussed, and relations with Coombs' unfolding techniques are explored.This work was supported in part by grant G-8864 from the National Science Foundation to the University of Pennsylvania. I wish to express my appreciation to Professors Robert R. Bush and Eugene Galanter, with whom I have had a number of very helpful discussions of these ideas.     

The role of individual differences in the accuracy of confidence judgments

Generally, self-assessment of accuracy in the cognitive domain produces overconfidence, whereas self-assessment of visual perceptual judgments results in underconfidence. Despite contrary empirical evidence, in models attempting to explain those phenomena, individual differences have often been disregarded. The authors report on 2 studies in which that shortcoming was addressed. In Experiment 1, participants (N= 520) completed a large number of cognitive-ability tests. Results indicated that individual differences provide a meaningful source of overconfidence and that a metacognitive trait might mediate that effect. In further analysis, there was only a relatively small correlation between test accuracy and confidence bias. In Experiment 2 (N = 107 participants), both perceptual and cognitive ability tests were included, along with measures of personality. Results again indicated the presence of a confidence factor that transcended the nature of the testing vehicle. Furthermore, a small relationship was found between that factor and some self-reported personality measures. Thus, personality traits and cognitive ability appeared to play only a small role in determining the accuracy of self-assessment. Collectively, the present results suggest that there are multiple causes of miscalibration, which current models of over- and underconfidence fail to encompass.     

An individual differences analysis of the self-teaching hypothesis

The self-teaching hypothesis suggests that children learn orthographic structure of words through the experience of phonologically recoding them. The current study is an individual differences analysis of the self-teaching hypothesis. A total of 40 children in Grades 2 and 3 (7-9 years of age) completed tests of phonological recoding, word identification, and orthographic knowledge. The relation of phonological recoding and word identification was significantly mediated by orthographic knowledge. Furthermore, two aspects of orthographic knowledge (perhaps word-specific and general orthographic knowledge) mediated different variance shared between phonological recoding and word identification. Results support an individual differences version of the self-teaching hypothesis and emphasize the importance of phonological recoding in the primary curriculum.     

An analysis of fidgeting and associated individual differences

Fidgeting was defined as engaging in manipulations of one's own body parts or other objects, such actions being peripheral or nonessential to central ongoing events or tasks Two studies employed preliminary fidgeting questionnaires of 70 and 106 items, respectively, tapping a wide range of habitual behaviors Item selection and factor analyses led to the development of a final, 40-item, individual difference measure of fidgeting tendency which is balanced for response bias and has an alpha reliability coefficient of 89 Convergent and construct validity were supported by positive correlations between the fidgeting tendency measure and measures of tendencies to engage in extraneous activities (consuming alcoholic drinks, cigarette smoking, eating, daydreaming, restlessness, insomnia) while preoccupied with certain situations and tasks These findings implied that fidgeting is an activity overflow and that it is more probable when the organism's physical activity is constrained by the central or focal act Fidgeting tendency also correlated positively with binge eating and with physical activity In two additional studies, questionnaire fidgeting tendency scores correlated positively with direct observations of fidgeting by subjects and with peer predictions Personality correlates of fidgeting tendency were well defined More fidgety persons were more unpleasant and more arousable (i e, more anxious or hostile) Fidgeting tendency did not correlate significantly with subject sex or with arousal-seeking tendency     

Cognitive processes and individual differences in judgments relevant to drunk driving

The present study explored cognitive processes in judgments of drunkenness relative to legally allowable blood alcohol levels for driving. Judgments were based on the manipulation of three cues in hypothetical scenarios in a 3 X 4 X 3 factorial design (Type of Drink X Number of Drinks X Time to Consume). In addition, personality and behavioral characteristics influencing the accuracy of judgments of drunkenness relative to true blood alcohol levels were examined. Results indicated the presence of several misperceptions and inappropriate response tendencies that potentially can be modified with educational efforts.     

An individual differences analysis of interdimensional additivity in multidimensional scaling

Comparative judgments of the dissimilarity between schematic faces varying on 1, 4, 7, or 10 binary attributes were obtained under two instructional sets. Using the Tucker-Messick procedure, three subgroups of like-perceiving Ss were isolated and the nature of cue-utilization by each described. Perceptual independence of attributes was demonstrated both within and between instructional sets for Subgroups 1 and within instructional sets for Subgroup 2. The Subgroup 3 results indicated an interaction of the attributes. Data from the Shot cognitive elements test differentially characterized Subgroups 1 and 2, but did not uniquely characterize Ss requiring more complex models for the combination of attributes. The study illustrates the possible usefulness of an individual differences approach to the study of selective attention and information processing.     

Optional processes in similarity judgments

This research investigates the nature of similarity relations among three pairs of interacting dimensions: (1) the integral dimensions of auditory pitch and loudness, (2) the configurai dimensions of paired parentheses, and (3) the cross-modally corresponding dimensions of visual position and auditory pitch. We evaluated the rules by which information from each dimension combines in similarity judgments. Our claim is that, when judging similarity, processes that are obligatory, or what we call mandatory processes, can commingle with processes of choice, or what we call optional processes. By varying instructions, we found strong evidence of optional processing. Instructions to rate overall similarity encouraged subjects to attend to stimuli as wholes and led to a Euclidean rule in similarity scaling. Instructions to focus on dimensions encouraged subjects to consider each stimulus dimension separately and led to a city-block rule. We argue that optional processes may obscure mandatory ones, and so need to be identifled-beforernandatory processes can be understood.     

Attentional interference in judgments of musical timbre: individual differences in working memory

Researchers have shown that working memory is related to a variety of high-level cognitive processes. However, the results of recent research have suggested that may be because of its role in attentional control. In the present experiment, the authors investigated that hypothesis by using an attentional interference task with musical stimuli. Listeners were asked to monitor one ear for either a clarinet or violin tone and to ignore any information in the other ear. On some of the trials, they heard only one tone and on other trials, either the same instrument in both ears or different instruments. Individual differences were measured in working memory and musical experience. The results showed more attentional interference in the different-instrument condition for participants with lower working memory scores, which suggested that working memory involves the ability to control attention to inhibit irrelevant information.     

Instability of individual differences in the association between confidence judgments and memory performance

There are large individual differences in the degree of association between the accuracy of memories and subjective confidence in those memories. Are these differences stable within the same test, and between alternate forms of a test? In Experiment 1, college students were tested on 3 recognition memory tasks, then retested 2 weeks later on alternate forms of the same tasks. The relationship between confidence judgments and recognition performance displayed low split-half stability and low alternate-forms stability. A second experiment with elderly adults replicated these findings. In a third experiment, college students recalled answers to general knowledge questions and rated confidence in the correctness of each answer. Individual differences in the association between confidence and recall performance were not stable across the odd- and even-numbered items on the test. These data indicate the need for the development of procedures that will produce stable estimates of individuals’ metacognitive accuracy.     

A multidimensional scaling analysis of judged similarity of complex forms from two task situations

Ss provided judgments of pairwise stimulus similarities for 21 12-turn random forms in two experimental tasks: a scaling task, involving a variant of the method of graded dichotomies, and a sorting task, which simply required Ss to categorize the forms. The grouped data from both tasks, when analyzed using nonmetric multidimensional scaling techniques, yielded five-dimensional configurations with euclidean distances. The correspondence of these two spaces, assessed using canonical correlations, was extremely good. The psychological dimensions derived from both tasks were related to two sets of physical measures on the forms: the factor space suggested by Brown and Owen and a set of more basic physical measures. Physical cues of greatest importance involved size, dispersion, angularity, and rotation measures. The value of the tasks and the utility of the Brown and Owen measures were discussed.     

An individual differences analysis of ability and strategy influences: age-related differences in associative learning

The relationships among abilities, strategies, and performance on an associative learning task were investigated for young (aged 17 to 34) and older adults (aged 60 to 82). Participants received extensive practice on a noun-pair task in which they could use a visual-scanning strategy or a memory-retrieval strategy. Older adults were more likely to use the scanning strategy. Age differences were reduced when comparisons were made only for participants using a retrieval strategy. Associative memory was predictive of learning on the task, and semantic memory access speed was predictive of practiced performance. Practiced performance on a memory-search task that also required associative learning was predictive of practiced noun-pair performance. Models of ability-performance relationships for skill acquisition are discussed.     

Happiness as a belief system: individual differences and priming in emotion judgments

Three studies involving 104 undergraduates sought to examine how an individual's level of life satisfaction organizes their knowledge concerning the self's emotions. Participants judged the self's positive and negative emotions within a computerized task. Key results sought to determine whether judging two positive emotions in a consecutive sequence speeds the second judgment--a pattern of priming that would suggest a tighter, more interconnected structure in semantic memory related to one's positive emotions. As expected, individual differences in life satisfaction predicted the magnitude of this priming effect (Studies 1 & 2), which appeared to be unique to judgments of the self's emotions (Study 3). The results indicate that happy, relative to less happy, individuals organize information concerning their positive emotions in a qualitatively different and tighter semantic manner.     

Relational similarity and the nonindependence of features in similarity judgments

Four experiments examined the hypothesis that simple attributional features and relational features operate differently in the determination of similarity judgments. Forced choice similarity judgments ("Is X or Y more similar to Z?") and similarity rating tasks demonstrate that making the same featural change in two geometric stimuli unequally affects their judged similarity to a third stimulus (the comparison stimulus). More specifically, a featural change that causes stimuli to be more superficially similar and less relationally similar increases judged similarity if it occurs in stimuli that already share many superficial attributes, and decreases similarity if it occurs in stimuli that do not share as many superficial attributes. These results argue against an assumption of feature independence which asserts that the degree to which a feature shared by two objects affects similarity is independent of the other features shared by the objects. The MAX hypothesis is introduced, in which attributional and relational similarities are separately pooled, and shared features affect similarity more if the pool they are in is already relatively large. The results support claims that relations and attributes are psychologically distinct and that formal measures of similarity should not treat all types of matching features equally.     

Optional processes in similarity judgments.

This research investigates the nature of similarity relations among three pairs of interacting dimensions: (1) the integral dimensions of auditory pitch and loudness, (2) the configural dimensions of paired parentheses, and (3) the cross-modally corresponding dimensions of visual position and auditory pitch. We evaluated the rules by which information from each dimension combines in similarity judgments. Our claim is that, when judging similarity, processes that are obligatory, or what we call mandatory processes, can commingle with processes of choice, or what we call optional processes. By varying instructions, we found strong evidence of optional processing. Instructions to rate overall similarity encouraged subjects to attend to stimuli as wholes and led to a Euclidean rule in similarity scaling. Instructions to focus on dimensions encouraged subjects to consider each stimulus dimension separately and led to a city-block rule. We argue that optional processes may obscure mandatory ones, and so need to be identified before mandatory processes can be understood.