Abstract: List of contributors Preface Introduction: psychophysical and cognitive aspects of categorical perception: a critical overview S. Harnad Part I. Psychophysical Foundations of Categorical Perception: 1. Categoric perception: some psychophysical models R. E. Pastore 2. Beyond the categorical/continuous distinction: a psychophysical approach to processing modes N. A. MacMillan Part II. Categorical Perception of Speech: 3. Phonetic category boundaries are flexible B. H. Repp and A. M. Liberman 4. Auditory, articulatory, and learning explanations of categorical perception in speech S. Rosen and P. Howell 5. On infant speech perception and the acquisition of language P. D. Eimas, J. L. Miller and P. W. Jusczyk Part III. Models for Speech Categorical Perception: 6. Neural models of speech perception: a case history R. E. Remez 7. On the categorization of speech sounds R. L. Diehl and K. R. Kluender 8. Categorical partition: a fuzzy-logical model of categorization behaviour D. W. Massaro Part IV. Categorical Perception in Other Modalities and Other Species: 9. Perceptual categories in vision and audition M. H. Bornstein 10. Categorical perception of sound signals: facts and hypotheses from animal studies G. Ehret 11. A naturalistic view of categorical perception C. T. Snowden 12. The special-mechanisms debate in speech research: categorization tests on animals and infants P. K. Kuhl 13. Brain mechanisms in categorical perception M. Wilson Part V. Psychophysiological Indices of Categorical Perception: 14. Electrophysiological indices of categorical perception for speech D. L. Molfese 15. Evoked potentials and color-defined categories D. Regan Part VI. Higher-order Categories: 16. Categorization processes and categorical perception D. L. Medin and L. W. Barsalou 17. Developmental changes in category structure F. C. Keil and M. H. Kelly 18. Spatial categories: the perception and conceptualization of spatial relations E. Bialystok and D. R. Olson Part VII. Cognitive Foundations: 19. Category induction and representation S. Harnad Author index Subject index.

Abstract: (1990). Social Identification, Self-Categorization and Social Influence. European Review of Social Psychology: Vol. 1, European Review of Social Psychology, pp. 195-228.

Abstract: Principles of Cortical Organization The Locales, Varieties and Uses of Maps Sense and Movement Categorization, Generalization and Memory Speech and Language Developmental and Theoretical Principles.

Abstract: This paper presents a cognitive categorization model of intercultural management that focuses on interaction between an expatriate manager and a host country subordinate. The paper outlines some of the effects that culture may have upon the content and structure of schemas, the extent to which automatic versus controlled information processing occurs, and the use of the model to examine convergence of cognitive structures through intercultural dynamics.

Abstract: There are far fewer kinds of elements (such as words) in a natural language than there are kinds of things in the universe If, therefore, the languages people speak are related to the universe their speakers live in, a primary function of the various kinds of elements constituting a language is to allow the much more varied kinds of things that populate the universe to be categorized in specific ways A "prototype" approach to linguistic categories is a particular way of answering the question of how this categorization operates It involves two claims First, that linguistic categorization exploits principles that are not specific to language but are validly used for "cognitive processing" in general Secondly, that a basic principle by which cognitive and linguistic categories are organized is the "prototype principle", whereby elements are assigned to a category not because they exemplify properties that are absolutely required of each one of its members, but because they exhibit certain properties in virtue of which a particular member of the category has been established as the best example (or "prototype") of its kind The development of the prototype approach into a satisfactory body of theory obviously requires both that its empirical base be enriched, and that its conceptual foundations be clarified These are the areas where this volume, in its 26 essays, makes original contributions The first two parts contain discussions in which various linguistic phenomena are analyzed in ways that make essential use of prototype notions The last two parts contain discussions in which prototypicality itself becomes the object, rather than the instrument, of analytical scrutiny

Abstract: According to Markman and Wachtel, children assume that nouns pick out mutually exclusive object categories, and so each object should have only one category label. While this assumption can be useful in word learning, it is not entirely reliable. Therefore, children need to learn when to and when not to make this assumption. 6 studies examined whether knowledge about hierarchical organization of categories and about cross-language equivalents for object labels can help children limit their use of this assumption appropriately. These studies revealed that adults as well as children resisted assigning 2 novel names to the same object in some situations. By age 4, children also seemed to know enough about categorization to accept 2 names for an object if the names picked out categories from different levels of a hierarchy (e.g., animal and lemur) but not if they picked out categories from the same level (e.g., lemur and seal). Moreover, monolingual as well as bilingual children seemed to know enough about languages to accept 2 names for the same object if the names clearly came from different languages. Together, these findings suggest that even preschool children can make use of knowledge about language and categorization to fine tune the mutual exclusivity assumption in order to use it effectively in word learning.

Abstract: Categorizing people into social groups mediates many processes of interest to social psychology, including stereotyping as well as perceivers' affective and behavioral reactions to the categorized target persons. Though researchers have often assumed that categorization depends on the similarity of the target to an abstracted category prototype, exemplar-based categorization may also be important under some circumstances. We demonstrate that prototype- and exemplar-based social categorization can be empirically distinguished and that socially realistic manipulations can lead perceivers to weight one or the other process more heavily. Perceivers who learn about group prototypes before encountering individual group members (as might occur through social learning of a stereotype) engage in more prototype-based processing, relative to perceivers who encounter group members at the outset. Implications for person memory and social categorization processes, as well as for intergroup relations, are discussed.

Abstract: Recent research suggests that preschool children approach the task of word learning equipped with implicit biases that lead them to prefer some possible meanings over others. The noun-category bias proposes that children favor category relations when interpreting the meaning of novel nouns. In the series of experiments reported here, we develop a stringent test of the noun-category bias and reveal that it is present in children as young as 2 years of age. In each experiment, children participated in a 5-item match-to-sample task. Children were presented with a target item (e.g., a cow) and 4 choices, 2 of which belonged to the same superordinate category as the target (e.g., a fox and a zebra) and 2 of which were thematically related to the target (e.g., milk and a barn). In Experiment 1 we demonstrate that novel nouns prompt preschool children to attend to superordinate-level category relations, even in the presence of multiple thematic alternatives. In Experiment 2, we ascertain that the bias is specific to nouns; novel adjectives do not highlight superordinate category relations. In Experiment 3, we demonstrate the noun-category bias in 2-year-olds. The nature and utility of the noun-category bias are discussed.

Abstract: Research on object concepts has identified one level of abstraction as "basic" in cognition and communication. We investigated whether concepts for routine social events have a basic level by replicating the converging operations used to investigate object concepts. In Experiment 1, subjects were presented with event names from a taxonomy and were asked to list the actions comprising the event. Many more actions were listed at the middle than at the highest taxonomic level, without a further increase at the most specific level, paralleling the pattern of superordinate-, basic-, and subordinate-level object concepts. From these action lists, brief stories were composed for each event. In Experiment 2, subjects made pairwise similarity judgments on the stories. The mean similarity of events increased with specificity, as expected. But differentiation of categories (within-category similarity compared to between-category similarity) was highest for super-ordinates, contrary to results with object categories. In Experiment 3, subjects were fastest in recognizing actions as belonging to events named at the basic level. In Experiment 4, subjects predominantly chose basic-level terms to name stories. We conclude that event taxonomies do show basic-level structure, albeit a less sharply defined and less stable structure than in object taxonomies. The benefits and hazards of extending models of object concepts to other entities, such as social events, are discussed.

Abstract: The roles of function, reminding, and exemplar variability in categorization of a physically dissimilar object were studied with 3-month-old infants trained to move a crib mobile by kicking. Performance on a transfer test with a motionless novel object provided evidence of categorization. In Experiments 1 and 2, infants, like adults, initially categorized novel objects on the basis of physical appearance, but only if trained with multiple exemplars, after delays of 1 and 7 days. In Experiment 3, prior knowledge of an object's functional properties overrode physical dissimilarity as the basis for categorization and enabled reminding of the classification response 2 weeks later. In Experiment 4, postevent contingency information overrode physical and functional properties as the basis for categorization. These findings indicate that expectations and goals influence infants' category decisions and raise the possibility that infants of 3 months respond by analogy.

Abstract: This article examines decision processes in the perception and categorization of stimuli composed of the separable psychological dimensions, orientation and size. The randomization technique (Ashby & Gott, 1988) of general recognition theory, which allows accurate estimation of a subject's decision boundary in a categorization task, is used in 4 experiments. Even though the stimulus components are clearly separable, it was found that ubjects were not constrained to use separable response strategies, nor were they constrained to attend to distance to the prototypes. Instead, they used decision rules that were nearly optimal, even if this required information integration or for the Ss to attend to higher level category properties such as component correlation. Language: en

Abstract: Semantic and cognitive development were studied in eight Korean and French-speaking children, and these results were compared with results for 12 English-speakers. The children received object- permanence, means-ends and categorization tasks and their develop ment of related linguistic forms, disappearance and success/failure words and a naming spurt, was recorded. There were close and specific relations between these semantic and cognitive developments. However, non-English-speakers used very different forms from English-speakers to encode disappearance, success and failure; in particular, Korean-speakers used verbs. This suggests that children may have been motivated to acquire these words because of their cognitive significance. Moreover, both categorization and naming developed later in the Korean-speakers than in English-speakers and French-speakers. This may be due to the fact that verbs are more perceptually salient in Korean than nouns. This difference between the language groups also suggests tha...

Abstract: This article examines the bases children of different ages use to categorize products. Data from children ages 4 to 10 indicate that the use of perceptual attributes as a basis for categorizing products decreases with age, whereas the use of underlying attributes to categorize products increases with age. These findings provide a conceptual replication of earlier findings from developmental psychology. Moreover, the findings suggest that younger children's failure to consider underlying attributes can be traced to common types of processing deficits. Theoretical implications arising from these observations and directions for future research are discussed.

Abstract: In two experiments, typists and nontypists were compared in affectively evaluating pairs of letter combinations in a forced-choice paradigm. Within each pair, one combination would be typed with the same finger, the other with different fingers.

Abstract: An apparatus capable of sensing the presence of objects in its environment, categorizing these objects without a prior description of the categories to be expected, and controlling robotic effector mechanisms to respond differentially to such objects according to their categories. Such responses include sorting objects, rejecting objects of certain types, and detecting novel or deviant objects. The invention includes a device called a 'classification n-tuple' (of which a 'classification couple' is a special case) capable of combining signals from two or more sensory modalities to arrive at the classification of an object.

Abstract: A rational analysis tries to predict the behavior of a cognitive system from the assumption it is optimized to the environment. An iterative categorization algorithm has been developed which attempts to get optimal Bayesian estimates of the probabilities that objects will display various features. A prior probability is estimated that an object comes from a category and combined with conditional probabilities of displaying features if the object comes from the category. Separate Bayesian treatments are offered for the cases of discrete and continuous dimensions. The resulting algorithm is efficient, works well in the case of large data bases, and replicates the full range of empirical literature in human categorization.

Abstract: Within the realms of cognitive studies, spatial structure is one of the few domains where attempts to trace mental representations from the level of sensory input conditions through conceptual structure to their lexical and grammatical organization seem to be feasible and revealing. Presenting a linguist's approach to the meaning and use of spatial dimensional terms, the paper aims to demonstrate why and how the semantic analysis of these linguistic items has to be justified in terms of nonlinguistic conceptual structure formation, which in turn has to be shown to derive from categorized perceptual input. Regarding framework and approach, the paper supplements Manfred Bierwisch's recent article on Comparison inyS, 6: 1.57-93 and 2.101-146. As to substance, it is argued that the structure of conceptual knowledge of spatial objects can plausibly be modelled by means of object schemata which result from two interacting categorization grids called Primary Perceptual Space and Inherent Proportion Schema. Offering an analysis which draws on linguistic theorizing, the paper is meant as an invitation to psycholinguists and psychologists for discussion and cooperation.

Abstract: Categorization and concept formation are critical activities of intelligence. These processes and the conceptual structures that support them raise important issues at the interface of cognitive psychology and artificial intelligence. The work presumes that advances in these and other areas are best facilitated by research methodologies that reward interdisciplinary interaction. In particular, a computational model is described of concept formation and categorization that exploits a rational analysis of basic level effects by Gluck and Corter. Their work provides a clean prescription of human category preferences that is adapted to the task of concept learning. Also, their analysis was extended to account for typicality and fan effects, and speculate on how the concept formation strategies might be extended to other facets of intelligence, such as problem solving.

Abstract: Triage in the Emergency Department is the process whereby patients are sorted on the basis of their illness or injury, to decide their needs and priority for treatment. The increasing workload of Emergency Departments throughout the world, together with increasing public and professional expectations of the quality and immediacy of care being provided in those Departments, have produced the need for triage. Formalization of the process of triage results not only in improved clinical care for patients, but also in a means of categorising patients in Emergency Departments for administrative and research purposes. The search for a reliable and agreed means of categorization has as yet not been successful. This study was designed to describe a system of categorization of patients in an Emergency Department; to test the repeatability of that categorization both within the study institution and other institutions; to test its validity in terms of the outcome of patients; and to use the categorization to describe prospectively the association of urgency with certain characteristics of patients in Emergency Departments. The study firstly used a written collection of triage profiles to test agreement between observers, secondly analyzed the performance of the categorization in all patients attending an Emergency Department over a twelve month period, and finally compared the patients' outcomes and the systems comparative validity in a stratified sample of patients drawn from the total patient population. The study demonstrated the categorization to have significant repeatability within observers, but not as good repeatability between individuals. The categorization was also shown to be highly predictive of patient mortality, time spent in hospital, time spent in Intensive Care and the frequency of certain types of investigations and procedures. The categorization also was correlatable with other known and tested severity indices such as Injury Severity Score, Trauma Score, Coronary Prognostic Index, and Asthma Severity Scores. On the basis of this predictability, the association of urgency with certain patient characteristics was shown. Patients with high urgency assessments were demonstrated to be significantly older, more frequently male and naturally to present relatively more often at nights and after hours. The more urgent patients more frequently had 'medical' diagnoses as opposed to 'trauma' diagnoses which were more frequent in the less urgent patients. Acute non-traumatic surgical, psychotic and behavioral problems were relatively rare. These findings have significance for Emergency Medicine, in that firstly they provide a standard means of categorization of patients with demonstrable repeatability and validity. Secondly, they provide a means of identifying the needs of individual patients with respect to the allocation of personnel and resources. Thirdly, they clearly demonstrate the areas of need, for staffing and rostering purposes. Finally, by improving the description of workload in Emergency Departments, they enable the selection and training of personnel to be more accurately targeted to meet patient needs.

Abstract: Categorization processes are central to many human capabilities; e.g., language, reasoning, problem solving. The concept of categorization is also at the base of many kinds of phenomenon which AI researchers have attempted to model; e.g., induction, analogy, and the use of causal models. Most approaches to induction can be characterized on a single dimension such as model driven, “top-down” to data driven, “bottom-up.” At the one end a large amount of preconstructed information (knowledge rich) is used while on the other end the featural similarity is analyzed of a given set of objects or events in the absence of other knowledge structures. These two kinds of approaches, represented recently by explanation-based learning (EBL) and similarity-based learning (SBL), conflict in terms of the proper approach to categorization and construction of causal theories. One view central to the present approach is that featural information is instrumental in formation of knowledge structures. Knowledge structures can be more general than objects and can possess more complex information than features (e.g., abstract concepts, actions, relations). Such knowledge structures are hypothesized to be both created and further manipulated by the SBL mechanism that learned them in the first place. The present approach is related to the discovery of category structure and the use of feature intercorrelations and their interaction with generalization, inheritance, retrieval, and memory organization.