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Individual differences in strategy choices: good students, not-so-good students, and perfectionists.

Consistent individual differences were found in first graders' strategy choices in addition, subtraction, and reading (word identification). Differences were present along 2 dimensions: knowledge of problems and stringency of thresholds for stating retrieved answers. Cluster analyses indicated that children could be classified into 3 groups: good students, not-so-good students, and perfectionists. Perfectionists were children who had good knowledge of problems and set very high thresholds for stating retrieved answers, good students also had good knowledge of problems but set lower thresholds, and not-so-good students had less good knowledge of problems and set low thresholds. Differences among the 3 groups were evident on measures not included in the cluster analysis as well as measures that were. Further, the groups differed in standardized achievement test performance 4 months after the experiment in ways consistent with the experimental analysis. The pattern of individual differences was similar in 2 experiments with different samples of children and problems and different methods for assessing strategy use. The results illustrated how detailed cognitive models can contribute to understanding of individual differences.