Abstract: This experiment was designed to test the hypothesis that intergroup discrimination in the minimal group paradigm is related to self-esteem. According to Social Identity Theory, intergroup discrimination is a strategy for achieving self-esteem via social competition aimed at increasing the positive distinctiveness of one's own group. However, other elements of the procedure, such as categorization into groups, or the opportunity to engage in a meaningful experimental task irrespective of its value for social competition, might also affect self-esteem. One hundred thirty-five undergraduates were randomly assigned to eight concurrent experimental conditions. A two-way multivariate analysis of variance on the core design produced a significant interaction effect, whereby categorized subjects who had the opportunity to discriminate between groups and noncategorized subjects who did not discriminate showed higher self-esteem than did both categorized subjects who could not engage in discrimination and noncategorized subjects who could discriminate. These results support social identity theory and also suggest that social categorization by itself may constitute a threat to self-esteem that can be resolved via social competition. Results from the supplementary conditions support the conclusion that it is intergroup discrimination, and not merely the completion of an experimental task, that redeems self-esteem.

Abstract: This study investigated the independent effects of power differentials on intergroup behaviour. Using a variant of Tajfel's minimal group paradigm (Tajfel and Turner, 1979), subjects were arbitrarily categorized into groups of differing power (0-100 per cent) at two levels of salience. Subjects were asked to distribute resources to ingroup and outgroup others using Tajfel's matrices. Intergroup perceptions, group identifications and self-reported strategies constituted our other dependent measures. Minimal group results, replicated in equal power conditions, were systematically eliminated in unequal power conditions on the matrix measures but not on the intergroup perception measures. Dominant group members were more discriminatory, felt more comfortable and satisfied than subordinate group members. Though consistent with Social Identity Theory (Tajfel and Turner, 1979), results suggest we may also have identified boundary conditions for minimal group discrimination. Without power, social categorization does not lead to effective discrimination.

Abstract: The author obtained a longitudinal psychiatric history from 30 patients with proven Cushing's syndrome. Twenty-five (83%) of the patients met strict diagnostic criteria for an episode of affective disorder during the course of their endocrine disturbance. Twenty patients met criteria for endogenous depression and eight patients also reported an episode of mania or hypomania. Schizophrenic syndromes were not evident, although two patients met criteria for a psychotic depression. Patients frequently attempted to minimize or conceal serious psychiatric disturbance, including a suicide attempt. Typical affective syndromes occurred in patients with adrenocortical tumors as well as in those with ACTH-dependent Cushing's syndrome.

Abstract: CALLANAN, MAUREEN A. How Parents Label Objects for Young Children: The Role of Input in the Acquisition of Category Hierarchies. CHILD DEVELOPMENT, 1985, 56, 508-523. Young children readily learn categories at the basic level, but they have difficulty organizing categories into hierarchies. Parents may influence this acquisition through the information they provide about categories at different levels. Adults use basic level terms in naming objects for children. They also may "anchor" children at the basic level by not using superordinate or subordinate terms for an object unless it is also labeled with a basic level tenn. However, these labeling patterns could be accounted for by a confounding of familiarity with category level. Basic level terms are the most familiar to children, and parents may use them for that reason, rather than to provide information about levels. 2 studies were conducted in which mothers taught concepts to their 2-4-year-old children with pictures that varied in familiarity. The anchoring effect was partially replicated. When teaching superordinates, mothers used basic ostension more than superordinate ostension, regardless of the familiarity of the basic level names for the pictures. However, there was no such anchoring effect when subordinate categories were taught. Further, mothers' teaching of superordinate categories contrasted with their teaching of basic and subordinate categories in other ways: superordinate terms were used often with groups of objects rather than single objects, and explicit statements of inclusion occurred only when superordinate categories were being taught. The results suggest that children must learn basic and subordinate categories through ostensive labeling, but that they are given extra infonnation that may help them to learn superordinate categories.

Abstract: Two experiments examined the respective role of the cerebral hemispheres in face perception and the nature of their contribution depending on task demands and on the spatial-frequency composition of the stimuli. Sixteen faces of members of the subjects' department were presented as stimuli, with men and women, and professors and nonprofessors being equally represented. In Experiment 1, high-resolution black-and-white photographs of faces were used in three reaction-time tasks: verbal identification, manual membership categorization, and manual male/female categorization, in a within-subject design. Identification and membership categorization were significantly better performed in right-visual-field presentations, whereas the male/female categorization yielded a nonsignificant left-visual-field superiority. In Experiment 2, two versions of the same faces were used: digitized low-pass (0 to 2 cycles/degree of visual angle) and digitized broad-pass (0 to 32 cycles/degree) faces. Broad-pass faces produced the same laterality pattern as in Experiment 1, while low-pass faces were better processed in left-visual-field presentations for all three tasks. The results suggest that the two hemispheres play a role in face perception, and their contribution may vary as a function of the task demands and of the spatial-frequency components of the incoming information.

Abstract: Pigeons and other animals can categorize photographs or drawings as complex as those encountered in ordinary human experience. The fundamental riddle posed by natural categorization is how organisms devoid of language, and presumably also of the associated higher cognitive capacities, can rapidly extract abstract invariances from some (but not all) stimulus classes containing instances so variable that we cannot physically describe either the class rule or the instances, let alone account for the underlying capacity. In contrast, with other contingencies of reinforcement, pigeons will not extract abstract rules of categorization; they will instead learn to identify visual stimuli down to small details, and they will retain much of what they learned for a year and more. How animals can shift between abstraction and photographic retention, and whether or not the two modes can be unified under a single theory are questions that help define the boundaries of knowledge about animal intelligence.

Abstract: Two studies assessed the organization and basis for children's categories of emotion. In one, children (N = 240) from 2 to 5 years of age and adults (N = 60) chose facial expressions that exemplify such emotion categories as fear, anger, and happiness. In the other (N =100), they grouped expressions differing in arousal level or pleasure-displeasure according to perceived similarity. Preschoolers demonstrated more knowledge of emotion than had been seen in previous investigations, in which they were said to be inaccurate in categorizing expressions of all but a few emotions. The results fit a model of emotion categories in which the boundaries separating different categories are more fuzzy than distinct, and in which the categories are interrelated in a systematic order, an order based on their degree of pleasure and arousal. Children's categories were not identical to those of adults, however; categories of the youngest children were broad, admitting as members expressions similar in pleasure and arousal...

Abstract: Some common clinical statements about patients with personality disorder are examined for their implications in the choice of category concepts for classifying personality. Clinicians seem to assume that personality categories are imprecise and that membership is probabilistic. These assumptions run counter to those of current classifications. The fact that most cases of personality disorder show features of more than condition creates difficulties for categorical systems. Dimensional systems are frequently proposed as a solution to this problem. Such an approach is rejected at the present time since there is no consensus regarding basic dimensions. Polythetic and prototypic categories are examined as alternatives. It is suggested that prototypic categorization provides an approach that is more in accord with clinical judgement. This approach, based upon Wittgenstein's concept of family resemblances, is better able to accommodate the imprecise or fuzzy nature of personality categories, although it does require some modification to the way categories are defined, and to the way diagnostic reliability is assessed.

Abstract: This paper presents an evidential approach to knowledge representation and inference wherein the principle of maximum entropy is applied to deal with uncertainty and incompleteness. It focuses on a restricted representation language - similar in expressive power to semantic network formalisms, and develops a formal theory of evidential inheritance within this language. The theory applies to a limited, but we think interesting, class of inheritance problems including those that involve exceptions and multiple inheritance hierarchies. The language and the accompanying evidential inference structure provide a natural treatment of defaults and conflicting information. The evidence combination rule proposed in this paper is incremental, commutative and associative and hence, shares most of the attractive features of the Dempster-Shafer evidence combination rule. Furthermore, it is demonstrably better than the Dempster-Shafer rule in the context of the problems addressed in this paper. The resulting theory can be implemented as a highly parallel (connectionist) network made up of active elements that can solve inheritance problems in time proportional to the depth of the conceptual hierarchy.

Abstract: The purpose of this study was to investigate whether infants spontaneously form categories during the prelinguistic period and whether these categories are based on the same principles as adult basic-level categories. A new methodology, using a functional use measure as the determinant of category composition, was employed in a case study of one infant's horn category. Results indicated that this category met Schlesinger's (1982) criteria for a prelinguistic category and that the category was based on similarity relationships, as adult categories are.

Abstract: Past theories concerned with communicative competence have assumed that perceiver's evaluations of the competence of a communicative performance are based on a conception of the “ideal communicator.” Psychological theory on categorization implies that this assumption is most viable if conceptions of “prototypes” relevant to competence in general (“the communicatively competent person”) are rich in defining characteristics relative to their logical superordinate (“the skilled person”), yet distinct from other skill-related prototypes (such as “the artistically talented person”), and if conceptions of prototypes relevant to competence in specific interactive situations are also relatively rich in defining characteristics, but similar to one another. Analysis of freely elicited lists of characteristics for categories within a taxonomic hierarchy for skill support these implications, showing that people's conceptions of “communicative competence” are organized in the manner most conducive to their use as the basis for competence evaluation. Results also point out the critical role played by concrete, rather than abstract, characteristics in differentiating among general and situation-specific prototypes.

Abstract: An approach to the socialization process is proposed that stresses the perceptual—cognitive activities of socializing adults. Parental categorization of descriptions of child behavior was examined. Forty pairs of white, middle-class parents with children of both sexes twice sorted sentences (obtained from another sample of parents) that described the social behavior of early-school-age children. Half of the respondents sorted behavior descriptions attributed to a boy; for the other halt, the same behavior descriptions were attributed to a girl. Multidimensional scaling and hierarchical clustering analyses of the measures of psychological distance derived from the sorting task revealed a strong tendency toward evaluative categorization in all conditions of sorting. Three components of evaluation were identified (i.e., Good—Bad Social Behavior, Encourage-Change, Mature-Immature). Four other possible schemas used by parents to structure cognitively the behavior descriptions were suggested by inspection of th...

Abstract: This article will profile five interesting cases of children with learning disabilities and auditory processing problems. These children have met a rather stringent criteria in terms of being classified as learning disabled. All subjects had normal peripheral hearning and speech discrimination ability in quiet bilaterally, with the exeption of Case 2. Each received extensive educational, psychological, and speech and language evaluations in addition to our audiological work-up. However, we will focus only on the audiological evaluations. Following each case, we will discuss the possible correlations between the presumed etiology and the unique audiological pattern on the central test battery. These five cases represent various kinds of central auditory profiles, with associated etiological correlates, which provide a categorization system for these children.

Abstract: Recent research on social cognition suggests that lifelike visual and vocal information about a person may strongly mediate the impact of prior social categorical knowledge on social judgements. Other research, however, on the contribution of visual cues to impression formation, suggests that they have relatively little impact. This study sought to resolve these conflicting findings by examining the effect of visual cues on social judgements when subjects possess prior social categorical knowledge varying in salience to the experimental task. Videotaped target interviews were monitored by observers in either sound and vision or sound only, and measures were taken of the targets' perceived personality, their ‘actual’ and ‘predicted’ social performance, and social acceptance by observers. Whilst salience of categorization strongly influenced the quality of judgements, visual cues had little if any effect. However, visual cues strongly influenced subjects' confidence in all three sets of judgements, sound and vision subjects being consistently more confident than their sound only counterparts. The findings are discussed in relation to previous research in both social cognition and visual cues.

Abstract: The process of group categorization, as suggested by Tajfel and Turner's (1979) theory of intergroup comparison, was examined under conditions of intergroup conflict in Northern Ireland. The theory predicts that under “normal” conditions groups have a need to distinguish themselves from others. The present study investigates how individuals in Northern Ireland under extreme environmental pressures to identify both their own and other groups, can use learned stereotypic cues in making such categorizations. Results suggested that such limited information was highly effective in the process of categorization, with both Protestant and Catholic subjects exhibiting significant agreement and confidence in identifying unknown persons on the basis of stereotypic cues Conflicting information was found to reduce subject's confidence levels, with conflicting Catholic cues being more disruptive than Protestant ones

Abstract: A marked correspondence is found to relate the categories of infant wavelength discrimination and the ethnographic distribution of adult color terms. The structure of the infant category system accounts for at least 75% of the variance in the world ethnographic categories (P less than 0.001). Such a correspondence is predicted to be favored by natural selection when perceptual mechanisms interact with their associated cultural traits.

Abstract: The present investigation examined the role of familiarity in the categorization process. Subjects (N = 111) were asked to recall statements made by strong or weak ingroup (same sex) and outgroup (opposite sex) applicants for medical residency programs and to evaluate the target applicants. The category relevance of the social context was accentuated by using gender-like residency programs. There were no effects of category familiarity in recall, consistent with the finding of Taylor, Fiske, Etckoff, and Ruderman (1978). An ingroup polarization effect was obtained: Strong, same-sex applicants were evaluated more favorably and weak, same-sex applicants, more unfavorably than opposite-sex applicants. These results support Tesser's (1978) model of attitude polarization. Discrepancies between these findings and the outgroup polarization effects obtained by Linville and Jones (1980) are discussed in terms of the mediating influence of category relevance and outgroup novelty in the relationship between...

Abstract: Various recurring themes in the history of the subject are reviewed. In the context of adaptation to a complex environment, one precondition for survival must be a capacity for object identity, which may be the most basic form of categorization. Evidence will be presented that suggests that the capacity is not learned. In considering learned associations among categorized items, a distinction is made between reflexive and reflective processes: that is between those associations in which a cue or signal provides an unambiguous route to the response, no matter how complex that route may be, in contrast to those in which learned information must be ordered and reordered `in thought'. An example of one experimental approach too the latter is provided. Finally, the problem of conscious awareness is considered in terms of stored categorical knowledge and associations, on the hand, and a system that monitors them, on the other. Neurological evidence of disconnections between these different levels is reviewed.

Abstract: Visual inspection and categorization of facial appearances constitute the most frequent and useful technique for measuring facial activity. The techniques developed, however, have different units with varying characteristics. In this paper, I discuss categorical and scalar units for facial measurement and show the relationship of categorical units listed by different researchers.

Abstract: Forty-eight students with no previous exposure to probability or statistics read one of three texts that varied in the emphasis placed on rote and conceptual learning of basic concepts of elementary probability. A qualitative analysis of errors on a postinstruction test employed a model of problem solving whose stages were categorization of the problem, retrieval of the appropriate formula, and translation of values from the problem into the formula. Variations in performance on problems requiring the same formula for solution were largely attributable to surface features that affected the ease of categorization and translation. Students who read a text that emphasized conceptual learning tended to be less sensitive to surface features, which parallels results regarding novices and experts in various content domains.

Abstract: This paper reports a machine induction program (WITT) which attempts to model human categorization. Properties of categories that human subjects are sensitive to include, best or prototypical members, relative contrasts between putative categories, and polymorphy (niether necessary or sufficient features). This approach represents an alternative to traditional Artificial Intelligence (AI) approaches to generalization and conceptual clustering which tend to focus on necessary and sufficient feature rules, equivalence classes, and search and match algorithms. The present approach is shown to be more consistent with human categorization while potentially including results produced by more traditional clustering schemes. Applications of this categorization approach are also discussed in the domains of Expert systems and Information retrieval.

Abstract: An experiment was designed to show that some categories, called Type C categories, are mediated by an abstract, interpretively derived conceptual base. To this end, each of four groups of subjects ranked 10 sentences (instances) in terms of how well they illustrated the figurative meaning of a proverb (Proverb group), or how well they illustrated the meaning of an excellent interpretation of the proverb (Excellent Interpretation group), or a poor interpretation of the proverb (Poor Interpretation group), or an unspecified, unstated underlying meaning (Control group). The Excellent Interpretation groups' rankings correlated highly with standard ranks established by the Proverb group, but the Poor Interpretation group's and the Control group's ranking were uncorrelated with these two group's rankings. Apparently, the subjects in the Proverb group accomplished their rankings by using a conceptual base or microtheory similar in meaning to the interpretation used by the Excellent Interpretation group. Discussion centered on the question of whether the Classical, Probabilistic, or Exemplar Views of categorization (Smith & Medin, 1981) could account for the results. It was argued that they could not, basically because Type C categories are more dependent upon interpretive processes than the more perceptually based Type P categories to which these views have traditionally been applied.