The goal of this unified theory of human reasoning is to specify what constitutes reasoning and to characterize the psychological distinction between inductive and deductive reasoning. The theory views reasoning as the controlled and mediated application of three processes (encoding, comparison and selective combination) to inferential rules. (JAZ)

This study evaluated the diagnostic validity of a task measuring abstract categorization ability in learning disabled (LD) and non-LD children. Data showed that the component of abstract category knowledge that best disciminates LD children from non-LD, is the knowledge of how members of abstract categories differ from each other. (Author/JAZ)

The information-processing approach and results of research on spatial ability are analyzed. Performance consists of a sequence of distinct mental operations that seem general across subjects, and can be individually measured. New interpretations for some classical concepts in psychological testing and procedures for abilities are suggested.…

Current studies of cognition emphasize the contrast between two approaches to analysis of individual differences. It is concluded that the cognitive components approach incorporates the cognitive correlates approach, avoids the inadequacy of correlational methods, and models individual differences on various dimensions of cognitive functioning.…

Major visuospatial and verbal abilities were assessed for 197 10-year-olds in Hong Kong and 170 10-year-olds in the United Kingdom. The Hong Kong subjects resembled their Japanese counterparts in having high Searman's "g," exhibiting abstract reasoning ability, high spatial ability, high perceptual speed, and low word fluency. (SLD)