The Cattell-Horn-Carroll (CHC) model is a comprehensive model of the major dimensions of individual differences that underlie performance on cognitive tests. Studies evaluating the generality of the CHC model across test batteries, age, gender, and culture were reviewed and found to be overwhelmingly supportive. However, less research is available…

As part of a long term project relating individual differences in performance on paper and pencil tests of intellectual aptitude and achievement to differences observed in laboratory studies of cognition, data have been collected comparing test scores with simple choice reaction times. The three studies summarized here suggest that the…

A 15-stage pyramidal test and a 40-item two-stage test were constructed and administered by computer to 111 college undergraduates. The two-stage test was found to utilize a smaller proportion of its potential score range than the pyramidal test. Score distributions for both tests were positively skewed but not significantly different from the…

The Early Childhood Inventories Project (ECIP) was initiated to originate aptitude/achievement type inventories which could assess very specific behaviors of young children, particularly disadvantaged children. In practice these inventories are "non-specific" type criterion-referenced measures. This first aspect of the project involved…