Bell Curve

152 Cognitive Chses and Social Behavior Schooling 1 53graduates was 115, and the mean of people getting medical degrees andPh.D.s was about 125.*' The book, published in 1972, was based on clinicalexperience in the 1950s and 1960s. This summary is virtually identicalto the story told by the NLSY for whites (who correspond mostclosely with the college population in the 1950s and early 1960s). Themean 1Q of high school graduates was 106, the mean of college graduateswas 116, and the mean of people with professional degrees was 126.The relative roles of socioeconomic status and IQ in getting a bachelor'sdegree for youths of the late 1970s and 1980s are shown in the figurebelow.For white youths, being smart is more importantthan being privileged in getting a college degreeProbability of getting a bachelor's degree80% -40% -30% -20% -105%-0%Very low(-2 SDs)As parenral SES goesfrom low to highNote: For computing the plot, age and either SES (for the black curve) or IQ (for the Faycurve) were set at their mean values.Two broad implications of these results stand out. The first is suggestedby the way that both curves hug the bottom throughout the lefthandside of the graph. The combination of average-or-below parentalSES or average-or-below IQ meant that the odds of getting a college de-gree are minuscule. The second broad implication is that parental SESis important but not decisive. In terms of this figure, a student with verywell-placed parents, in the top 2 percent of the socioeconomic scale,had only a 40 percent chance of getting a college degree if he had onlyaverage intelligence. A student with parents of only average SESlowermiddle class, probably without college degrees themselves-whois himself in the top 2 percent of 1Q had more than a 75 percent chanceof getting a degree.Once again, the common stereotype of the talented-but-disadvantaged-youth-denied-educational-opportunitydoes not seem to exist insignificant numbers any longer. Only seven-tenths of 1 percent of whitesin the NLSY were both "prime college material" (IQs of 1 15 or above)and markedly disadvantaged in their socioeconomic background (in thebottom quartile on the SES index). Among this tiny group, it is truethat fewer than half (46 percent) got college degrees. Those who didnot, despite having high IQs, may be seen as youths who suffered fromhaving a disadvantaged background. But recall that this group consistsof only four-tenths of 1 percent of all white youths. A category of worthywhite young persons denied a college education because of circumstancessurely exists to some degree, but of such small size that it doesnot constitute a public policy problem.What about another stereotype, the untalented child of rich parentswho gets shepherded through to a degree? Almost 5 percent of whiteyouths had below-average 1Qs (under 100) and parents in the top quartileof socioeconomic status. Of those, only 12 percent had gotten collegedegrees, representing just six-tenths of 1 percent of white youths.Judging from these data, the common assertion that privileged whiteparents can make sure their children do well in school, no matter what,may be exaggerated.SUMMING UPThe act of leaving high school before graduating is a rare event amongwhite youths, conspicuously concentrated in the lowest quartile of cognitiveability. Among those who drop out, both socioeconomic statusand cognitive ability are involved. Most dropouts with above-averageintelligence go back to get a GED.~~" But socioeconomic status remains