Major proposals that psychologists have made about how humans segment their world into categories are reviewed. The anthropological literature that bears on the same issues is explored, noting its implications for psychological theory. Cross-cultural data provide substantial constraints for theories of category coherence. (SLD)

Relative prevalence of stereotyped behaviors was studied with 246 children and adults with developmental disabilities. Two staff members completed a 54-item checklist assessing stereotyped behaviors, abnormal focused affections, compulsions, rigidity, savant skills, and defensiveness. Factor analyses produced weak evidence for a general stereotypy…

Three studies examined preschool children's understanding of categorical hierarchies, testing their ability to form categories at different levels of generality and to include the same objects in multiple categories. Found that, contrary to the implications of previous studies, two- and three-year olds appear to have both categorization skills.…

Four experiments involving 159 undergraduates examined beliefs about the nature of water, testing a strong version of psychological essentialism that takes belief in an essence to be the primary determinant of category membership and word use. Results suggest that essentialist beliefs may not fully explain category membership judgments. (SLD)

A proportional reduction in loss (PRL) measure for reliability of categorical data is explored for the situation in which each of "N" judges assigns a subject to one of "K" categories. Calculating a lower bound for reliability under more general conditions than had been proposed is demonstrated. (SLD)

The use of cluster analysis, a multivariate classification technique, is advocated as a framework to guide the purposive selection of projects for multiple-case study research. A cluster analysis of a contrived data set demonstrates how the procedure is performed, and advantages and limitations are discussed. (SLD)

The relationship between Children's Depression Inventory (CDI) scores and major depression, conduct disorder, and anxiety disorders was studied for 107 psychiatric inpatients aged 12 to 18 years. Findings support total CDI score, rather than factor scores, as the most practical measure for classifying participants as depressed or not. (SLD)

Two experiments were conducted with 124 undergraduate and graduate students to investigate the interaction between strategy use and accessibility to relevant knowledge. Variations in relevant knowledge accessibility significantly affected strategy use on the first memorization trial, and ease of use on the first trial affected maintenance of the…

The relative consistency in categorization by age-equivalent groups of preoperational and concrete-operational first graders was assessed across two categorization tasks employing color drawings of exemplars of superordinate artifact categories. Results are discussed in terms of the utilization and acquisition of knowledge about superordinate…

It is argued that the axes of the Learning Style Inventory and Learning Style Questionnaire are not conceptually aligned. More accurate comparison involves the degree of similar classification of learning styles, as illustrated in the modest but similar degree of classification for 44 graduate and undergraduate students. (SLD)

Developed typology of 156 convicted driving-while-intoxicated (DWI) offenders using cluster analysis and external validation procedures. Derived typology from four variables (alcohol dependence severity, psychiatric severity, bad-driving index, social instability) selected to maximize feasibility of performing treatment matching with DWI…

Analysis of staff perceptions of classes of reinforcers and aberrant behaviors of 480 people with predominantly severe or profound mental retardation suggested 8 classes of reinforcers (e.g., consumable, play) and 5 classes of maladaptive behaviors (irritability, lethargy, stereotypy, hyperactivity, and inappropriate speech). Each class of…

Reports results of a study that examined Library of Congress topical subject headings and subdivisions in a large bibliographic database. Creation of a new machine-readable authority file of topical subdivisions and enhancements to the existing subject authority file are recommended to assist in assignment and validation of subdivided headings.…

This case study of how the museum community is trying to select standards for data interchange between museum systems reviews the work of the Museum Computer Network's committee on the Computer Interchange of Museum Information (CIMI) and reflects on the issues confronting CIMI as it tries to exploit information technology standards as a strategy.…

Three experiments explored four and seven year olds' and adults' knowledge of taxonomy, including horizontal relations between items at the same hierarchical level and vertical relations between items at different hierarchical levels. Results showed that four year olds' taxonomic knowledge was restricted to one type of horizontal relationship. (BC)