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T B Ward

Publications and source records attributed to T B Ward.

10 recordsLinked to original sources
PubMed1990

Children and adults learn family-resemblance categories analytically.

3 experiments examined the modes of processing used by children and adults in learning family-resemblance categories. The materials were cartoon faces (Experiments 1 and 2) and bugs (Experiment 3) divided into categories that possessed no single defining attributes, but rather several characteristic attributes that were each partially predictive of category membership. The categories were structured so that a holistic mode of processing in which the individual did not selectively weight any given attributes could have led to success. Nevertheless, preschoolers (Experiments 2 and 3), first and third graders (Experiment 1), and adult college students (all experiments) all exhibited primarily analytic modes of learning that consisted of single- and dual-attribute approaches. Although the proportion of analytic learners among the preschoolers was lower than among the adults in Experiment 3, in no case were holistic modes of learning evident. The results are discussed in terms of their implications for young children's apparent relative success in learning natural categories. It is suggested that children's success in learning real-world categories may be based, in part, on an interaction between a basically analytic processing style and natural category structures that provide many partially informative attributes.

Adult↗
PubMed1990

Further comments on the attribute availability hypothesis of children's category learning.

Kemler Nelson raises several important issues regarding children's category learning in her commentary on Ward, Vela, and Hass. The points of agreement in our positions concern the extreme complexity of the phenomenon. The points of disagreement that are addressed in this reply concern Kemler Nelson's assertions that (a) children are, in general, holistic processors, (b) a holistic processing model provides a better account of children's category learning than the attribute availability model, and (c) that Ward et al. have overestimated the extent of analytic processing and underestimated the extent of holistic processing by young children. All of these points are challenged in the present paper.

Attention↗
PubMed1989

Classification behavior and measures of intelligence: dimensional identity versus overall similarity.

Individuals tend to adopt either analytic or holistic modes of categorizing objects. In two studies, we examined the relation between these categorization tendencies and cognitive abilities as measured by standard psychometric instruments. The participants in both studies were pretested with a restricted classification task in which it was possible for them to classify simple stimuli by dimensional identity or overall similarity. Those making a large number of either type of categorization were then tested with subtests of the WAIS-R and with the Raven's progressive matrices. Across both studies, the analytic individuals (many dimensional identity classifications) scored higher than the holistic individuals (many overall similarity classifications) on some but not all of the subtests. The results are consistent with the idea that holistic modes of categorization may be more "primitive" than analytic modes. The findings are discussed in terms of the association between categorization mode and either general or specific cognitive abilities.

Adult↗
PubMed1989

What makes a vibble a vibble? A developmental study of category generalization.

Young children appear to know when a novel label for a novel object is a common noun. The present study was concerned with the properties of a named object that children assume to be true of other members of the category that is specified by such a noun. Preschoolers, second graders, and college students were shown drawings of objects and given nonsense labels for those objects. They then viewed other objects that varied from the labeled ones along 4 particular attributes and were asked to decide if those other objects should also receive the same label. Preschoolers focused mostly on single attributes in making category decisions, and their choices of attributes were evenly distributed among the 4 types. Older individuals primarily exhibited multiple attribute rules. The results are discussed in terms of developmental differences in the modes of processing that are used and in the types of knowledge that are brought to bear on the word learning situation.

Attention↗
PubMed1986

Classifying color materials: children are less holistic than adults.

Much recent research indicates that children respond to materials which are separable for adults as though those materials were integral. The present studies examined differences between 5-year-olds and adults in the processing of integral materials. In Study 1, both children and adults made a majority of similarity classifications for those materials. However, the children were found to make fewer of those integral similarity classifications and more dimensional classifications than adults for materials varying in the integral dimensions of chroma and value. In Study 2, children's similarity judgments were also indicative of greater separability of those dimensions. For both children and adults, similarity ratings given in Study 2 were predictive of classification behavior in Study 1. Age differences in similarity ratings were also predictive of age differences in classification. The overall pattern of results is consistent with the idea that children's perception is neither more nor less holistic than that of adults. Whether children or adults are found to be more holistic depends on the nature of the material presented. With integral materials, young children respond in a manner which appears less holistic than that of adults.

Adult↗
PubMed1986

Classifying multidimensional stimuli: stimulus, task, and observer factors.

When observers decide how to classify stimuli, they often employ one of two types of information: identity along one particular dimension or overall similarity. The present studies examined interrelations among the factors which determine the use of these types of information. Participants' classifications of certain types of materials (e.g., size and brightness, length and density) revealed strong individual differences, were related to the individual's response tempo and selective processing ability, and were influenced by task demands. Classifications of other materials (e.g., saturation and brightness) did not reveal individual differences, were not affected by response tempo and selective processing ability, and were unaffected by changes in task demands. The former, but not the latter, types of materials have also been found to be influenced by developmental differences. The results are consistent with the idea that differences in response tempo and selective processing ability underlie observer differences (both individual and developmental) and that certain types of stimuli which are not susceptible to such influences set boundary conditions for observer differences. The results are discussed within an integral-to-separable model of processing.

Adult↗