Black–White differences on IQ and grades: The mediating role of elementary cognitive tasks Bryan J. Pesta a, ⁎ , Peter J. Poznanski b,1 a Department of Management, BU 439, Cleveland State University, 2121 Euclid Avenue, Cleveland, OH 44114, United States b Department of Accounting, BU 529, Cleveland State University, 2121 Euclid Avenue, Cleveland, OH 44115, United States Received 4 June 2007; received in revised form 21 July 2007; accepted 21 July 2007 Available online 23 August 2007 Abstract The relationship between IQ scores and elementary cognitive task (ECT) performance is well established, with variance on each largely reflecting the general factor of intelligence, or g. Also ubiquitous are Black–White mean differences on IQ and measures of academic success, like grade point average (GPA). Given C. Spearman's (Spearman, C. (1927). The Abilities of Man. New York: Macmillan) hypothesis that group differences vary directly with a test's g loading, we explored whether ECT performance could mediate Black–White IQ and GPA differences. Undergraduates (139 White and 40 Black) completed the Wonderlic Personnel Test, followed by inspection time and choice reaction time ECTs. Despite restriction of range, ECT performance completely mediated Black–White differences on IQ (d =.45). Group differences on GPA (d =.73), however, were larger and ECT performance did not mediate them. We discuss findings in light of Spearman's hypothesis. © 2007 Elsevier Inc. All rights reserved. A Black–White group difference on intelligence test scores has persisted in the literature for over 90 years. Currently, the group IQ mean for Blacks (85) remains about one-standard deviation below the group IQ mean for Whites (100; see, e.g., Neisser et al., 1996; Lynn, 2006; Rushton & Jensen, 2006). Though the difference exists, no consensus as to its cause is likely forthcoming. Some argue that research here is flawed because race- based classifications are invalid (see e.g., Sternberg, Grigorenko, & Kidd, 2005; Tate & Audette, 2001), or because a single, global IQ score cannot adequately represent human intelligence (see, e.g., Gardner 1983). Others argue that Black–White differences are real— due neither to cultural, nor test bias—and at least partly driven by genes (see, e.g., Herrnstein & Murray, 1994; Rushton & Jensen, 2005; Gottfredson, 2005a). The literature also shows that Blacks, on average, are less likely than Whites to attend college, and those that do have lower standardized test scores, grade point averages (GPAs), and higher dropout rates (Dreary, Strand, Smith, & Fernandes, 2007; Roth et al., 2001; U.S. Department of Education, 2001). Academic achievement and IQ, however, are strongly related. Gottfredson (2005b) summarized data showing a median correlation of .60 between standardized tests of school performance and IQ test scores (.80 when aggregating the different academic tests into a single composite; see also Gottfredson, 2004). Clearly, a large percentage of the variance in academic performance is Available online at www.sciencedirect.com Intelligence 36 (2008) 323 – 329 ⁎ Corresponding author. Tel.: +1 216 687 4749. E-mail addresses: b.pesta@csuohio.edu (B.J. Pesta), p.poznanski@csuohio.edu (P.J. Poznanski). 1 Tel.: +1 216 687 4764. 0160-2896/$ - see front matter © 2007 Elsevier Inc. All rights reserved. doi:10.1016/j.intell.2007.07.004