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W M Petrusic

Publications and source records attributed to W M Petrusic.

15 recordsLinked to original sources
PubMed2001

Testing architectures of the decision-confidence relation.

Two experiments examined the effect of rendering confidence judgments on the properties of the comparative decision process. In Experiment 1, participants worked for 12 sessions that required two-alternative perceptual, line-length comparisons. For sessions 1-4 and sessions 9-12, confidence judgments were not required. For sessions 5-8, participants provided confidence reports following each comparative judgment. The requirement of confidence judgments significantly increased decisional response time, suggesting that some confidence processing occurs in parallel with the primary decision process. Concomitantly, an examination of the properties of the time to determine confidence during sessions 5-8 revealed clear evidence of postdecisional confidence processing. These results were replicated in a second experiment requiring two-alternative comparative judgments of Canadian city populations. We conclude that confidence processing occurs both during the decision process and postdecisionally, and we discuss the implications of the present findings for current theories of confidence in human judgment.

Adult↗
PubMed1999

Realism of confidence in sensory discrimination.

Is there a common and general basis for confidence in human judgment? Recently, we found that the properties of confidence judgments in the sensory domain mirror those previously established in the cognitive domain; notably, we found underconfidence on easy sensory judgments and overconfidence on hard sensory judgments. In contrast, data from the Uppsala laboratory in Sweden suggest that sensory judgments are unique; they found a pervasive underconfidence bias, with overconfidence being evident only on very hard sensory judgments. Olsson and Winman (1996) attempted to resolve the debate on the basis of methodological issues related to features of the stimulus display in a visual discrimination task. A reanalysis of the data reported in Baranski and Petrusic (1994), together with the findings of a new experiment that controlled stimulus display characteristics, supports the position that the difference between the Canadian and the Swedish data is real and, thus, may reflect cross-national differences in confidence in sensory discrimination.

Adult↗
PubMed1998

Probing the locus of confidence judgments: experiments on the time to determine confidence.

Three experiments investigated the properties of the time to determine confidence to determine the processing locus for the judgment of confidence. Results suggest that when the primary decision is made under speed stress, confidence is determined postdecisionally and involves a memory-based, computational algorithm. This strategy frees the primary decision of processing time and permits the accurate diagnosis of decision errors. When the primary decision is made under accuracy stress, however, the determination of confidence is initiated, or can even be completed, during the primary decision process. This strategy permits confidence to be used in the adaptive regulation of the decisional parameters during the decision process but yields poorer diagnosticity of errors when they occur. The latter finding also implies that primary decision latencies include time to determine confidence, rendering such data difficult, if not impossible, to model empirically. Implications for contemporary decision models that provide a basis for confidence in human judgment are discussed.

Decision Making↗
PubMed1998

Similarity comparisons with remembered and perceived magnitudes: memory psychophysics and fundamental measurement.

At the outset, subjects learned to associate a label with each element in a set of perceptual magnitudes (visual extents), using traditional paired-associate learning methods. Subsequently, on some trials, subjects indicated which pair of two pairs of labels corresponded to the more similar perceptual referents, and, on other trials, they selected the more dissimilar pair. It is shown that these similarity comparisons satisfy the axioms (transitivity and intradimensional subtractivity) necessary to conclude that they are based on computation of the difference of the differences of analogue-based interval scale representations. The findings also permitted refutation of the idea that memory for elementary percepts arises from their reperception. Notably, the memory exponent was 0.697, but the perception exponent was 0.546, and the reperception idea requires that the memory exponent be the square of the perception exponent (0.546(2) = 0.298). Symbolic distance effects and enhanced response time-based semantic congruity effects, typically found with binary comparisons, extend the range of commonalties found between perceptual and memory psychophysics.

Humans↗
PubMed1997

Context, feedback, and the calibration and resolution of confidence in perceptual judgments.

The effects of variations in the global task difficulty context on judgmental confidence and confidence calibration were investigated in two experiments requiring perceptual comparisons. In Experiment 1, target judgments of moderate difficulty were embedded in a larger set of more difficult (hard context) or less difficult (easy context) judgments. Decisional response time on the target items was longer in the hard context condition, but there was no effect of difficulty context on target judgment confidence, accuracy, over/underconfidence, calibration, or resolution. In Experiment 2, each subject was exposed to three levels of local judgment difficulty. The global contextual difficulty manipulation involved varying the frequency with which the hard and easy judgments appeared, and the presence or absence of trial-by-trial response feedback was manipulated between subjects. As in Experiment 1, contextual difficulty affected decisional response times but not mean confidence ratings or accuracy. However, we found that providing feedback on a globally difficult task makes calibration worse. Also, resolution (the ability to differentiate correct from incorrect judgments) was found to be superior for easy judgments in a difficult context and for difficult judgments in an easy context. We discuss the implication of these findings for research on confidence and confidence calibration.

Adult↗
PubMed1995

On the calibration of knowledge and perception.

This study examined confidence judgements (i.e., calibration, resolution, and over/underconfidence) and response times in an intellectual knowledge task and a perceptual task requiring location comparisons. At each of four levels of judgement difficulty (i.e., Easy, Hard, Impossible and Misleading/Illusory), very similar properties were evident in the two tasks. The results are inconsistent with theories that assume a fundamentally different basis for confidence in human knowledge and perception.

Attention↗
PubMed1994

The calibration and resolution of confidence in perceptual judgments.

Confidence rating based calibration and resolution indices were obtained in two experiments requiring perceptual comparisons and in a third with visual gap detection. Four important results were obtained. First, as in the general knowledge domain, subjects were underconfident when judgments were easy and overconfident when they were difficult. Second, paralleling the clear dependence of calibration on decisional difficulty, resolution decreased with increases in decision difficulty arising either from decreases in discriminability or from increasing demands for speed at the expense of accuracy. Third, providing trial-by-trial response feedback on difficult tasks improved resolution but had no effect on calibration. Fourth, subjects can accurately report subjective errors (i.e., trials in which they have indicated that they made an error) with their confidence ratings. It is also shown that the properties of decision time, conditionalized on confidence category, impose a rigorous set of constraints on theories of confidence calibration.

Feedback↗
PubMed1992

Semantic congruity effects and theories of the comparison process.

Two experiments requiring comparisons of point locations on the line demonstrate that the magnitude of the response-time-based congruity effect parallels the form of the macro and the micro speed-accuracy trade-off function. This is predicted from the evidence accrual class of theories but is contrary to either the propositionally based semantic coding theory or the expectancy view. Very large accuracy-based congruity effects with comparisons of point locations in the plane are evident. Congruity effects arise because the duration of each evidence accrual is increased and the quality of the information is reduced as the distance of the stimulus representations from the instruction-activated reference point increases. This evidence accrual view is extended to account for the properties of perceptual and symbolic comparisons.

Adult↗
PubMed1992

The discriminability of remembered magnitudes.

Psychometric functions and the associated indices of discriminative performance (i.e., the point of subjective equality [PSE], just noticeable difference, and Weber fraction) were obtained with the method of constant stimuli using perceptual and remembered line-length standards. Three important results were obtained. First, comparisons with a perceptual or a remembered standard were sensitive to variations of absolute stimulus differences with a common ratio; that is, Weber's law was violated. Second, relative to discriminative performance with the longest and shortest remembered standards, comparisons involving mid-range remembered standards displayed increased variability in the PSE and inflated Weber fractions, characteristic of a reduction in the quality of the memorial representation. Finally, large and negative time-order errors (TOE) were observed for successive line judgments but not for those involving remembered standards. The implications of these findings for research concerned with the relationships between perception and memory, as well as the TOE phenomenon, are discussed.

Adult↗
PubMed1992

Metacognition in psychophysical judgment: an unfolding view of comparative judgments of mental workload.

An experiment is reported in which it was found that when subjects were required to indicate which of two visual extents was more difficult to categorize as "long" or "short," they executed these categorizations and then measured the distance of the representation of each stimulus from the long-short category boundary; the stimulus nearer the boundary was judged to be the more difficult. When they were requested to indicate which was easier to categorize, they selected the alternative that was farther. Coombs's theory of data (1952, 1964) and his unfolding theory of preferential choice (1950, 1964) provided the conceptualization of metacognition in this psychophysical task context. Strong support for the probabilistic version of unfolding theory was obtained from the observed selective effects of laterality on the levels of stochastic transitivity attained for various classes of triples and the reliably longer times for comparisons with bilateral pairs than with unilateral pairs. The semantic congruity effects obtained, together with the changes in the form of the relationship between probability and response time as a function of practice, can be best accounted for by an evidence accrual theory in which the distances from the active reference point are measured and compared with a criterion on each evidence accrual. No support is provided for the view that propositionally based semantic "ease"-"difficulty" codes serve as the basis for these metacognitive comparative judgments of ease and difficulty.

Adult↗
PubMed1989

Semantic congruity effects in perceptual comparisons.

Semantic congruity effects occur when, as in Experiment 1, for example, the time to select the shorter of two relatively short lines is faster than the time to select the longer; conversely, selection of the longer of two relatively long lines is faster than selection of the shorter. Semantic congruity effects are also demonstrated in experiments requiring comparisons of the heaviness of weights (Experiment 2) and horizontal extent (Experiment 3). In Experiment 1, the magnitude of the semantic congruity effect was larger under conditions emphasizing accuracy rather than speed and when the comparison was difficult. In fact, when comparisons were errorless, the effect was minimal (20 msec), thereby replicating previous failures to obtain the effect with supraliminal perceptual comparisons (Banks, Mermelstein, & Yu, 1982; Marschark & Paivio, 1981; Petrusic & Baranski, 1988a). In confirmation of Henmon's (1911) introspective analyses of psychophysical comparisons, Experiments 2 and 3 extend the range of the semantic congruity effect to include judgments of confidence. However, in each of the three experiments, semantic congruity effects were not evident with the response-accuracy measure. Finally, using highly confusable stimuli, in Experiment 3 the magnitude of the semantic congruity effect was shown to be larger for error than for correct response times. The implications of these findings for a decisional locus of the effect and for the semantic coding theory are discussed.

Attention↗
PubMed1978

Feedback versus an illusion in time.

The accuracy of many perceptual comparisons depends greatly on the order in which the to-be-compared stimuli are presented. With comparisons of durations around 300 ms, these presentation-order effects do not diminish, even with extended practice, when feedback about response accuracy is withheld. Providing such feedback greatly diminishes presentation-order effects and coincidentally produces substantial increases in response accuracy. The feedback acts in part through inducing response biases and in part through changes in sensitivity. The contradiction between studies which report time-order errors in duration comparison and those which do not is attributable to differences in the use of information feedback.

Discrimination, Psychological↗