Explorations of crystallized intelligence - Completion tests, cloze tests,and knowledge

An attempt is made to reconcile two historically important tools for the as sessment of intelligence and the prediction of academic achievement with ex tant theories of verbal-crystallized-knowledge aspects of adult abilities. A study of 167 adults ranging in age from 18 to 69 reasserts the importance of individual differences in completion test and doze test performance in accounting for both measures of crystallized intelligence (Gc) and four sca les of knowledge (biology, U.S. history, U.S. literature, and technology). The completion tests were found to account for all of the variance in Gc an d knowledge that the doze tests accounted for, and resulted in incremental predictive validity for both domains. In addition, completion and doze test s were found to have a suppressor effect on the relationship between Gc and Age. We note that C. Spearman's [The nature of "Intelligence" and the prin ciples of cognition. New York: MacMillan (1927).] assertion, namely that th e completion test had higher correlations with intelligence than any other measure. Our results suggest that abstract reasoning may be far less useful in predicting learning and performance than the completion test is. (C) 20 01 Elsevier Science Inc. All rights reserved.