Typicality effects in logically defined categories

Subjects learned to categorize geometric designs by some rule combining two features, x and y. When xy stimuli (stimuli with both features) are always positive, the rule (concept) is inclusive disjunctive; when xy stimuli are always negative, the rule is exclusive disjunctive. In three other experimental conditions, the probability of xy stimuli being positive during acquisition was .25, .50, and .75. In a variety of postacquisition tests, xy stimuli were chosen as prototypical despite their less than consistent occurrence in the positive category. Stimuli with one relevant feature (x or y), although consistently assigned to the positive category, were often evaluated as poorer examples of the concept. These results are interpreted in terms of a schema model in which information acquired during learning is organized according to probability density functions over feature dimensions. This theory appears to be general enough to accommodate the evidence from laboratory studies of both logical and natural concepts.     

Sex and sycophancy: Communication strategies for ascendance in same-sex and mixed-sex superior-subordinate dyads

The purpose of this study was to examine communication strategies for ascendance in same-sex and mixed-sex superior-subordinate dyads. The strategies, operationalized in terms of task and social facilitation, were derived from Bales' Interaction Process Analysis categories. Corollary data were collected relative to the subordinate's expected job satisfaction under male versus female supervision. Results indicated that (1) the perceived importance of task versus social facilitative strategies varied both within and across the four types of dyads, and (2) female subordinates expected to be more satisfied working under female supervision than did male subordinates.The authors would like to thank Ralph Kilmann and John Grant, Graduate School of Business, University of Pittsburgh, for their assistance in providing subjects for this study.     

The extent,nature, and utility of evaluating consumer satisfaction in community mental health centers

Evaluating consumer perceptions is a recent development in community mental health. The authors surveyed the 504 federally funded community mental health centers to discover the extent to which they assessed consumer satisfaction, the methods used to collect data, and the utility of the results. Of the 366 centers that responded, 48% had gathered consumer feedback in the previous 18 months, and most others planned to initiate such evaluations within a year. Methods of conducting the studies were extremely diverse. Respondents felt the results were useful and shared them primarily with agency personnel, rather than with outside funders, fellow agencies, or clients. The authors conclude that community mental health centers are evaluating consumer satisfaction more frequently than in the recent past, but this movement has not yet developed clear, standardized methods. Until evaluators consolidate their efforts this evaluation strategy will continue to have limited utility.     

Changes over time among homeless young people in drug dependency, mental illness and their co-morbidity

A cross-national survey was conducted among 358 recently homeless young people in Melbourne and Los Angeles. Drug dependence and mental illness were assessed at baseline, 6 and 12 months. At each time point, participants were classified as no condition, drug dependent, having a mental illness or dual condition. Low levels of drug dependence or mental illness or both were reported at each data point. Most young people were classified as neither drug dependent nor having mental illness at baseline and remained so for the 12-month period and few remained drug dependent, or had continuing mental illness or both. Half to two-thirds of young people classified as having one or both conditions were subsequently reclassified as "no condition". There was no evidence of a consistent pathway from either drug dependence or mental illness to co-morbidity. Most young people reported an absence of mental illness and/or drug dependence at each time point. Improvement from one or both conditions at each transition suggests it may be more effective to provide interventions to address drug dependence and mental health problems to young people early in their experience of homelessness.     

Bilateral saccades increase intrahemispheric processing but not interhemispheric interaction: Implications for saccade-induced retrieval enhancement

Retrieval of memories is enhanced when bilateral saccades are made immediately before attempting retrieval. One hypothesis is that saccades enhance retrieval by increasing interaction of the brain hemispheres. To test this, subjects viewed arrays of lateralized letters and indicated whether target letters matched either of two probe letters. Matching targets and probes were presented to either the same hemisphere (within-hemisphere trials) or separate hemispheres (across-hemisphere trials). Match detection requires interhemispheric interaction on across-hemisphere trials but primarily intrahemispheric processing on within-hemisphere trials. Subjects performed letter matching following saccades and a fixation control condition. Saccades increased match-detection accuracy on within-hemisphere trials only, suggesting that, counter to the hypothesis, saccades enhance intrahemispheric processing but not interhemispheric interaction. Across-hemisphere accuracy was higher, however, for subjects who were not strongly right-handed, versus those who were, and the absence of strong right-handedness may reflect greater interhemispheric interaction. We discuss implications for accounts of saccade-induced retrieval enhancement.     

Effects of handedness consistency and saccade execution on eyewitness memory in cued- and free-recall procedures*

Identifying characteristics that distinguish between people with relatively good versus poor episodic memory is an important goal of eyewitness-memory research, as is identifying activities that can improve people’s ability to retrieve episodic memories. Consistency of hand preference is a trait associated with the quality of people’s episodic memory and repetitive saccade execution is an activity known to improve people’s ability to retrieve episodic memories. These factors were examined in relation to cued and free recall of a staged criminal event. Individuals with inconsistent hand preference (versus consistent) remembered more on a cued-recall test and also freely recalled a larger amount of victim information. Repetitive saccade execution did not increase cued recall but did increase free recall of victim information. Theoretical implications are discussed, as is potential practical significance, with an emphasis on the size of the observed effects.     

Overconfidence in Probability and Frequency Judgments: A Critical Examination

The overconfidence observed in calibration studies has recently been questioned on both psychological and methodological grounds. In the first part of the article we discuss these issues and argue that overconfidence cannot be explained as a selection bias, and that it is not eliminated by random sampling of questions. In the second part of the article, we compare probability judgments for single events with judgments of relative frequency. Subjects received a target individual's personality profile and then predicted the target's responses to a series of binary questions. One group predicted the responses of an individual target, while a second group estimated the relative frequency of responses among all target subjects who shared a given personality profile. Judgments of confidence and estimates of relative frequency were practically indistinguishable; both exhibited substantial overconfidence and were highly correlated with independent judgments of representativeness.