Bell Curve

640 Appendix 5 Appendix 5 64 11991? For example, the average white taking the Literature achievementtest in 1980 had an SAT Verbal score that put him at the 80thpercentile of white testees; in 1991, he was at the 85thpercentile. Meanwhile,the average black taking the Literature achievement test in 1980had an SAT Verbal score that put him at the 88th percentile of all hlackSAT testees; in 1991, he was still at the 88th percentile of the hlack distribution.The difference between blacks and whites on the Literatureachievement test narrowed during that period, but, given where theblacks and whites were relative to the white and black SAT distributions,it seems unlikely that the narrowing was caused by changes in theself-selection that artificially raised black scores relative to whites. Tenof the thirteen achievement tests fit this pattern. In only three cases(European History, Physics, and German) did changes in the SAT Mathor Verbal scores indicate that the black pool had become differentiallymore selective. Only in the case of German was this difference largeenough to account plausibly for much of the black improvement relativeto whites.THE ACT. The College Board's major competitor in the college entranceexamination business is the American College Testing program,which has also shown decreasing differences between black and whitestudents who take the test, as summarized in the table below. ReJuc-creasing, suggesting that the increases in scores are not the result of amore selective test-taking population.THE GRADUATE RECORD EXAMINATION (GRE). The GRE is the equivalentof the SAT for admission to graduate school in the arts and sciences.Not many people in any cohort take the GRE, so the sample isobviously highly self-selected and atypical of the population. In 1988,for example, the number of white GRE test takers represented only 5.6percent of the 22-year-old white population; black test takers represented2.3 percent of its 22-year-old population. On the other hand, theproportions in 1988 were about the same as they were in 1979. The selfselectionprocess has remained fairly steady over the years, so it is worthat least mentioning the results, as shown in the table below. The GREBlack-White Difference in the GRE, 1979-1988White-Black Difference, in SDs1979 1988 ChangeVerbal 1.25 1.13 -.I2Math 1.28 1.13 -.I5Analytical 1.46 1.2 1 -.25Source. Graduate Record Examlnatlon Board.Black-White Difference in the ACT, 1970-199 1White-Black Difference, in SDs1970 1991 ChangeEnglish 1.14 .83 -.3 1Math .86 .77 -.09Science .97 .91 -.06Composite 1.12 .96 -. 16Source: ACT 1991, Tahles 1 4; Congressional Budget Office 1986, FIE. E-2.tions in the gap occurred in all the subtests between 1970 and 1991,with by far the largest reduction on the English subtest. The magnitildeof the overall change in the composite is about half the size of the reductionobserved in the black-white difference on the SAT. Like theSAT population, the ACT'S population of black test takers has been in-gap narrowed only slightly less than that for the SAT. Another positivenote is that the narrowing was achieved because black scores rose morethan white scores, not because white scores were falling.These results from national tests are echoed in state-level data fromTexas and North Carolina, as reported in the Congressional Budget Office'ssurvey of trends in educational a~hievement.~"verall, the evidenceseems clear beyond a reasonable doubt: On college entrance testsand national tests of educational proficiency, the gap between whitesand blacks remained large into the early 1990s, but it had been narrowingin the preceding decade or two. The optimist may argue that thetrend will continue indefinitely if improvements in the environmentand education for American blacks can be continued. The pessimist maynote that there seems to have been little narrowing since the mid-1980s,as we observed in the text for Chapter 13, and that the black-white IQ