The Bell Curve: Intelligence and Class Structure in American Life

by Richard J. Herrnstein

  Bits of national memorabilia like this reinforce an impression that is nearly universal in this country: American elementary and secondary education used to be better. The 1983 report by the Department of Education, A Nation at Risk, said so most famously, concluding that “we have, in effect, been committing an act of unthinking, unilateral educational disarmament.”2 Its chairman concluded flatly that “for the first time in the history of our country, the educational skills of one generation will not surpass, will not equal, will not even approach, those of their parents.”3

  We begin by affirming the conventional wisdom in one respect: The academic performance of the average American student looks awful at first glance. Consider illiteracy, for example. Some authorities claim that a third of the population is functionally illiterate.4 No one really knows—when does “literacy” begin?—but no matter where the precise figure lies, the proportion is large. As of 1990, 16 percent of the 17-year-olds still in school were below the level called “intermediate” in the National Assessment of Educational Progress (NAEP) reading test—in effect, below the threshold for dealing with moderately complex written material.5 Then one must consider that more than 20 percent of 17-year-olds had already dropped out of school and were not part of the sample,6 bringing us somewhere above 20 percent of the population who cannot use reading as a flexible tool of daily life.

  There is a profusion of horror stories in other subjects. Fewer than one in three American 17-year-olds in a nationally representative sample could place the Civil War within the correct half-century of its actual occurrence.7 Fewer than 60 percent of American 17-year-olds could correctly answer the item, “A hockey team won five of its 20 games. What percent of the games did it win?”8 More than 60 percent of adults in their early twenties cannot synthesize the main argument of a newspaper article.9 Forty-four percent of adult Americans cannot understand “help wanted” ads well enough to match their qualifications with the job requirements. Twenty-two percent cannot address a letter well enough to make sure the post office can deliver it.10

  Critics of American education also point to international comparisons. Between the early 1960s and the end of the 1980s, six major international studies compared mathematical competence, science knowledge, or both, across countries.11 The National Center for Education Statistics has conveniently assembled all of the results for the first five studies in a series of twenty-two tables showing the United States’ ranking for each scale. The results for the industrialized countries are easily summarized: In seven of the twenty-two tables, the United States is at the very bottom; in eight others, within two countries of the bottom; in four of the remaining seven, in the bottom half.12 The most recent study, conducted in 1991, found that the United States continued to rank near the bottom on every test of every age group for the math tests and near the middle on the science tests.13

  International comparisons need to be interpreted cautiously.14 But the most common defense for America’s poor showing is losing credibility. For years, educators excused America’s performance as the price America pays for retaining such a high proportion of its students into high school. But Japan has had as high a retention rate for years, and recently many European nations, including some that continue to outscore us on the international tests, have caught up as well.15

  The picture is surely depressing. But as we look back to the idealized America of the earlier part of the century, can we catch sight of American school children who, on average, would have done any better on such measures than the youngsters of today? A growing number of educational researchers are arguing that the answer is no.16 With qualifications that the chapter will explain, we associate ourselves with their findings. According to every longitudinal measure that we have been able to find, there is no evidence that the preparation of the average American youth is worse in the 1990s than it has ever been. Considerable evidence suggests that, on the contrary, education for the average youth has improved steadily throughout the twentieth century except for a period of decline in the late 1960s and early 1970s (which justified to some degree the alarming conclusions of the early 1980s) but from which the educational system has already fully recovered. How can we get away with these statements that seem so contrary to what everyone knows? We do it by means of that innocuous word, “average.”

  During the first half of the twentieth century, education for the average American young person improved steadily, partly because the average American young person spent more time in school than previously (Chapter 6). But much other evidence, marshaled convincingly by economist John Bishop, indicates a steady, long-term improvement in what Bishop calls “general intellectual achievement” that extended from the earliest data at the turn of the century into the 1960s.17 Even if we discount some of these results as reflections of the Flynn effect,18 it is impossible to interpret the data from 1900 to 1950 as showing anything other than some improvement. Then in the mid-1960s began a period of decline, as manifested most notably by the fall in SAT scores. Many people are under the impression that the decline was deep and permanent for the entire population of students. In reality, the decline for the average student was modest and recovery was quick. We know this first through the NAEP, begun in 1969, which we discussed with regard to ethnic differences in Chapter 13.19 When the first NAEP tests were given, the SAT score decline was in its fifth year and would continue for most of the next decade. The SAT is generally for a population concentrated at the upper end of the cognitive ability distribution, whereas the NAEP is for a nationally representative sample. While the scores for the population taking the SAT were still declining, the trendlines of the NAEP results were flat. The differences between the earliest NAEP scores in reading, science, and math (which date from 1969 to 1973, depending on the test) and the scores in 1990 are a matter of a few points and small fractions of a standard deviation, and scores often went up rather than down over that period.20

  SAT scores had started declining in 1964, but the NAEP goes back only to 1969. To reach back further for nationally representative data, we turn first to five almost completely unpublicized studies, known collectively as the national norm studies, conducted by the Educational Testing Service (ETS) in 1955, 1960, 1966, 1974, and 1983. In these tests, a short version of the SAT (the Preliminary Scholastic Aptitude Test, or PSAT) was administered to a nationally representative sample of American high school juniors. The results are summarized in the table below, adjusted so as to represent the mean score that all American juniors would have received on the SAT had they stayed in school for their senior years and had they taken the SAT.

  What SAT Score Decline? The Results of the National Norm Studies, 1955-1983

  Year Verbal Mean Math Mean

  Sources: Cole 1955; Chandler and Schrader 1966; Katz and others 1970; Jackson and Schrader 1976; Braun, Centra, and King 1987.

  1955 348 417

  1960 374 410

  1966 383 395

  1974 368 402

  1983 376 411

  These results say that American eleventh graders as of 1983 were, as a whole, roughly as well prepared in both verbal and math skills as they had been when the college-bound SAT scores were at their peak in 1963, and noticeably stronger in their verbal skills than they had been in the first norm study in 1955. The decline in verbal scores between the 1966 and 1974 tests was 15 points—only about .14 standard deviation. About half of that had been recovered by the 1983 test.21

  A third source is the Iowa Test of Educational Development (ITED), a well-validated test, equated for stability from year to year, that has been administered to virtually a 100 percent sample of Iowa’s high school students for fifty years. What may one learn from rural, white Iowa? For examining trends in educational outcomes over time, quite a bit. Iowa’s sample of students provides socioeconomic variance—even Iowa has single-parent families and welfare recipients. Paradoxically, Iowa’s atypical racial homogeneity (the population was more than 97 percent non-Latino white throughout the period
we are discussing) is an advantage for a longitudinal analysis by sidestepping the difficulties of analyzing trends for populations that are changing in their ethnic composition. In examining Iowa’s test scores over time, we may not be able to make judgments about how the education of minorities has changed but we have a good view of what happened over the last several decades for the white population.

  Test scores for high school students in Iowa increased from the early 1940s to the mid-1960s, dropped sharply from 1966 to 1978, but then rebounded, as shown in the figure below. We show the ninth-grade scores, which have been least affected by changes in dropout rates during the last fifty years. They show a steep rise through 1965 and an equally steep rise after 1977, reaching new heights from 1983 onward.22 The improvement has been substantial—on the order of half a standard deviation since the mid-1970s, and about .2 standard deviation above the previous high in 1965. The increase of 5.3 points from 1942 to 1992 may be interpreted as approaching one standard deviation.

  Evidence from other, independent sources is consistent with the story told by the national norm studies and the Iowa data. Project TALENT, the huge study of high school students undertaken in 1960, readministered its reading comprehension test in 1970 to another sample and found that a nationally representative sample of eleventh graders had gained slightly over its counterpart of 1960, during the same decade that saw the steepest decline in the SAT. Other data on state tests in Virginia, New York, Texas, and California, summarized by the Congressional Budget Office in its study of trends in educational achievement, cannot match the time range of the Iowa or SAT norm data, but, within their limits, they are generally consistent with the picture we have sketched.23 Even the international assessments are consistent. The United States had some of its worst results in the first international assessment, conducted in the early to mid-1960s when American SAT scores were near their peak.24 Since then, the national American averages have been, on balance, rising and the deficit in international comparisons shrinking.

  A half-century of Iowa tests: Improvement as the norm, the slump as a twelve-year aberration

  Source: Iowa Testing Program, University of Iowa.

  Taken as a whole, the data from representative samples of high school students describe an American educational system that was probably improving from the beginning of the century into the mid-1960s, underwent a decline into the mid-1970s—steep or shallow, depending on the study—and rebounded thereafter. Conservatively, average high school students seem to be as well prepared in math and verbal skills as they were in the 1950s. They may be better prepared than they have ever been. If U.S. academic skills are deficient in comparison with other nations, they have been comparatively so for a long time and are probably better than they were.

  TRENDS IN EDUCATION II: COLLEGE STUDENTS

  Having questioned the widespread belief that high school education today is worse on average than it used to be, we now reverse course and offer some reasons for thinking that it has gotten worse for one specific group of students: the pool of youths in the top 10 to 20 percent of the cognitive ability distribution who are prime college material. To make this case, we will focus on the best-known educational trend, the decline in SAT scores. Visually, the story is told by what must be the most frequently published trendlines in American educational circles, as shown below.25

  The steep drop from 1963 to 1980 is no minor statistical fluctuation. Taken at face value, it tells of an extraordinarily large downward shift in academic aptitude—almost half a standard deviation on the Verbal, almost a third of a standard deviation on the Math.26 And yet we have just finished demonstrating that this large change is not reflected in the aggregate national data for high school students. Which students, then, account for the SAT decline? We try to answer that question in the next few paragraphs, as we work our way through the most common explanation of the decline. To anticipate our conclusion, the standard explanation does not stand up to the data. We are left with compelling evidence of a genuine decline in the intellectual resources of our brightest youngsters.

  Forty-one years of SAT scores

  Source: The College Board. Scores for 1952-1969 are based on all tests administered during the year; 1970-1993 on the most recent test taken by seniors.

  The most familiar explanation of the great decline is that the SAT was “democratized” during the 1960s and 1970s. The pool of people taking the test expanded dramatically, it is said, bringing in students from disadvantaged backgrounds who never used to consider going to college. This was a good thing, people agree, but it also meant that test scores went down—a natural consequence of breaking down the old elites. The real problem is not falling SAT scores but the inferior education for the disadvantaged that leads them to have lower test scores, according to the standard account.27

  This common view is mistaken. To make this case requires delving into the details of the SAT and its population.28 To summarize a complex story: During the 1950s and into the early 1960s, the SAT pool expanded dramatically, but scores remained steady. In the mid-1960s, scores started to decline, but, by then, many state universities had become less selective in their admissions process, often dropping the requirement that students take SATs, and, as a result, many of the students in the middle level of the pool who formerly took the SAT stopped doing so. Focusing on the whites taking the SAT (thereby putting aside the effects of the changing ethnic composition of the pool), we find that throughout most of the white SAT score decline, the white SAT pool was shrinking, not expanding. We surmise that the white population of test takers during this period was probably getting more exclusive socioeconomically, not less. It is virtually impossible that it was becoming more democratized in any socioeconomic sense.

  After 1976, when detailed background data on white test takers become available, the evidence is quite explicit. Although the size of the pool once again began to expand during the 1980s, neither parental income nor parental education of the white test takers changed.29 After factoring in the effects of changes in the gender of the pool and changes in the difficulty of the SAT, we conclude that the aggregate real decline from 1963 to 1976 among whites taking the SAT was on the order of thirty-four to forty-four points on the Verbal and fifteen to twenty-five points on the Math. From 1976 to 1993, the real white losses were no more than a few additional points on the Verbal. On the Math, white scores improved about three or four points in real terms after changes in the pool are taken into account. Or in other words, when everything is considered, there is reason to conclude that the size of the drop in the SAT as shown in that familiar, unsophisticated graphic with which we opened the discussion is for practical purposes the same size and shape as the real change in the academic preparation of white college-bound SAT test takers. Neither race, class, parental education, composition of the pool, nor gender can explain this decline of forty-odd points on the Verbal score and twenty-odd points on the Math for the white SAT-taking population during the 1960s and 1970s. For whatever reasons, during the 1960s America stopped doing as well intellectually by the core of students who go to college.

  Rather than democratization, the decline was more probably due to leveling down, or mediocritization: a downward trend of the educational skills of America’s academically most promising youngsters toward those of the average student. The net drop in verbal skills was especially large, much larger than net drop in math skills. It affected even those students with the highest levels of cognitive ability.

  Does this drop represent a fall in realized intelligence as well as a drop in the quality of academic training? We assume that it does to some extent but are unwilling to try to estimate how much of which. The SAT score decline does underscore a frustrating, perverse reality: However hard it may be to raise IQ among the less talented with discrete interventions, as described in Chapter 17, it may be within the capability of an educational system—probably with the complicity of broader social trends—to put a ceiling on, or actually dampen, the realize
d intelligence of those with high potential.30

  TRENDS IN EDUCATION III: THE BRIGHTEST OF THE BRIGHTEST

  One more piece of the puzzle needs to be put in place. The SAT population constitutes a sort of broad elite, encompassing but not limited to the upper quartile of the annual national pool of cognitive ability. What has been happening to the scores of the narrow elite, the most gifted students—roughly, those with combined scores of 1400 and more—who are most likely to fill the nation’s best graduate and professional schools? They have gone down in the Verbal test and up in the Math.

  The case for a drop in the Verbal scores among the brightest can be made without subtle analysis. In 1972, 17,560 college-bound seniors scored 700 or higher on the SAT-Verbal. In 1993, only 10,407 scored 700 or higher on the Verbal—a drop of 41 percent in the raw number of students scoring 700 and over, despite the larger raw number of students taking the test in 1993 compared to 1972.31 Dilution of the pool (even if it were as real as legend has it) could not account for smaller raw numbers of high-scoring students. But we may make the case more systematically.

  The higher the ability level, the higher the proportion of students who take the SAT At the 700 level and beyond, the proportion approaches 100 percent and has probably been so since the early 1960s (see Chapter 1). That is, almost all 17-year-olds who would score above 700 if they took the SAT do in fact take the SAT at some point in their high school career, either because of their own ambitions, their parents’, or the urging of their teachers and guidance counselors. It is therefore possible to think about the students who score in the 700s on the SAT as a proportion of all 17-year-olds, not just as a proportion of the SAT pool. We cannot carry the story back further than 1967 but the results are nonetheless provocative, as shown in the next figure.32