Are There More Gifted People Than Would Be Expected in a Normal Distribution? An Investigation of the Overabundance Hypothesis

Abstract

Among some gifted education researchers, advocates, and practitioners, it is sometimes believed that there is a larger number of gifted people in the general population than would be predicted from a normal distribution (e.g., Gallagher, 2008; N. M. Robinson, Zigler, & Gallagher, 2000; Silverman, 1995, 2009), a belief that we termed the “overabundance hypothesis.” We tested this hypothesis by searching public datasets and the published literature for large representative datasets, 10 of which were found in 6 sources. Results indicated that the overabundance hypothesis was mostly unsupported by the data. Moreover, most datasets included approximately the same (or fewer) gifted individuals than would be predicted from a normal distribution. We conclude the article by exploring the theoretical reasons why the overabundance is likely untrue and why some might believe otherwise.

Keywords

intelligence giftedness normal distribution

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