Adventures in Intelligence Testing
by Clyde E. Noble
I HAVE BEEN asked to tell you something about the life and works of Dr. Frank Craig Joseph McGurk, an emeritus professor of psychology who is now retired and living in Florida. His adventures in testing the Culture Hypothesis make an absorbing tale of the perils and vicissitudes of doing research on psychological issues having social relevance.
Professor McGurk is a psychometric and clinical psychologist who has specialized for over 40 years in the fields of cognition, personality, and human differences. A native of Pennsylvania with Scottish and Irish roots, he was educated in the public and parochial schools of Philadelphia. During the depression years he attended on a four-year scholarship the famed Wharton School of Finance at Penn, receiving the BS degree in 1933.
Switching to psychology, McGurk earned his MA at the University of Pennsylvania in 1937 and his PhD at Catholic University in 1951. During the intervening years he saw service as a clinician with the Philadelphia General Hospital, Institute of the Pennsylvania Hospital for Mental and Nervous Diseases, Children’s Memorial Clinic of Richmond, and the U.S. Army in World War II. He is a long-time member of the American Psychological Association (APA) and of the Southern Society for Philosophy and Psychology (SSPP).
Professor McGurk’s academic appointments have included Catholic University, Lehigh, Montevallo, the U.S. Military Academy, and Villanova. His research has appeared in the Journal of Abnormal and Social Psychology, the Journal of Applied Psychology, the Journal of Educational Psychology, the Harvard Educational Review, the American Journal of Physical Medicine, and other well-known publications.
It was McGurk’s (1951) doctoral dissertation comparing the scholastic aptitude scores of American blacks and whites matched in socioeconomic status (SES), plus his subsequent articles in APA journals (McGurk, 1953a, 1953b, 1958) and in the magazine U.S. News and World Report (McGurk, 1956), which catapulted him to prominence, indeed notoriety, a full decade before Shockley, Jensen, or Herrnstein were branded as heretics. What McGurk did was to conduct the first empirical test of the Culture Hypothesis: i.e., the proposition of Otto Klineberg (1944), Ashley-Montagu (1945), and others that the significant black-white differences in mean test scores are not primarily biological but mainly due to social and economic inequalities. Because SES indices’ tend to favor Caucasian (C) students over Negro (N) students, proponents of the Culture Hypothesis argued in the 1940s that the mean C>N finding is principally the result of environmental rather than hereditary variables.
McGurk proceeded to draw samples of 426 Negro (N) and Caucasian (C) seniors from high schools in Pennsylvania and New Jersey. Next he paired them in age and SES. For SES he used 14 factors on the Sims SocioEconomic Scale. Then he computed his subjects’ aptitude test scores. Briefly, it turned out that the average race difference (C>N) persisted even though the subjects were equated on the variable hypothesized to be of prime importance; namely SES.
McGurk went further. He analyzed the 75 test items to see whether the score differences were similar on cultural and on noncultural questions. The former would be items calling for verbal information and memory whereas the latter would require numerical and reasoning abilities. McGurk did not leave the item selection to personal fancy. He took the pooled judgments of 78 psychologists, sociologists, and teachers as definitive of 37 cultural and 37 noncultural questions (one was judged neutral).
The result was that the shortfall of the black students was greatest on the noncultural questions. No Negro equaled the mean test score of the highest 10% of Caucasians on such culture-fair items. By contrast, on the culture-loaded, verbally-weighted items, the highest Negro score was exceeded by only 5 % of the Caucasians. Apparently, then, cultural questions do not penalize American blacks. Moreover, the racial discrepancy was greater at the upper SES levels that at the lower SES levels (McGurk, 1953a). Only 18% of the black elite did as well as the average for the white elite when both were in the top 25% of SES for each racial group. In the bottom 25% of SES the black/white overlap was 41% (McGurk, 1967). For groups of equivalent mean performance, of course, the statistical overlap would be exactly 50%. McGurk’s high SES black group scored significantly below his high SES white group, but the scores of his two low SES groups were not significantly different.
Thus, the data showed that as cultural opportunities increased the racial differences in scores also increased. Furthermore, verbally-weighted test questions appeared to improve Negroes’ performance relative to that of Caucasians. Recently Arthur Jensen (1973) hypothesized that the relevant variable affecting the black/white overlap in standard IQ tests is probably cognitive complexity. He defines this as the extent to which the items require abstraction, conceptualization and transformation of stimulus inputs. Most cultural questions are of low complexity.
The outcomes of McGurk’s research were manifestly inconsistent with what Otto Klineberg (1944) and Ashley-Montagu (1945) had led us to expect in the name of the Culture Hypothesis. An increase in SES ought to have decreased the mean score differences, according to Klineberg and Montagu, and cultural items should have been revealed as unfair and discriminatory. It is interesting to observe that McGurk refrained from denoting either his own special test or the nationally standardized IQ tests as measures of “intelligence,” preferring to speak neutrally of “psychological-test performance” (1956, p. 94); of “psychological tests … as predictive of differences in scholastic achievement” (1959, p. 55); and simply of “psychological test scores” (1967, p. 368). Certainly up to 1960 McGurk never even suggested a genetic alternative to the environmentalistic viewpoint. Of course, his enemies did just that, and they projected that notion on him (e.g., Klineberg, et al., 1956; McCord & Demerath, 1958); his rejections of the imputations are a matter of record (McGurk, 1958, 1959).
After 1960 McGurk began referring to biological factors in connection with racial, ethnic, mental, and psychic differences, but he maintained an operational stance vis-a-vis IQ until his latest essay (McGurk, 1975), in which he finally relented and wrote of “racial differences in intelligence” (p. 219), “intelligence test scores” (p. 219), “intelligence levels” (p. 234), and “relative intellectual status” (p. 235). Back in 1956, however, the country was in the throes of a serious social revolution. It was dangerous to contemplate the possibility of linkages between genetics, race, and intelligence. Nevertheless, despite his innocuous language Professor McGurk was harassed and threatened. Newspaper and magazine editorials (e.g., Boston Globe, New Republic) condemned his conclusions. He drew heavy fire from civil-rights and other political pressure groups. Two of these organizations (reportedly the B’nai B’rith and the NAACP) demanded that Villanova fire him. The Catholic administration of the University declined to go that far, but the hierarchy did officially silence him for 2 years, with an implied threat of excommunication should he disobey. These unsettling facts I have gleaned from the muzzled victim himself.
Eventually McGurk was forced out, only to find that numerous academic posts were closed to him. For example, I am told that the Chairman of the Department of Psychology at the University of Massachusetts rejected McGurk’s job application on the grounds that he could not possibly hire anyone who had written such a controversial dissertation. A noted professional society (the American Association of Physical Anthropologists) allegedly refused to admit Dr. McGurk because his controversial views might offend certain members of that organization. At first pilloried, he was eventually ignored by psychologists; citations of his work ceased. He had become a pariah in the land of the free.
Frank McGurk was down but not quite out. As a practicing Catholic he obeyed the Church’s gag order, but when the sentence expired he resumed his teaching and research activities. A book chapter appeared 10 years ago (McGurk, 1967), in which he reminded behavioral and social scientists that the Culture Hypothesis was still unconfirmed, and that there had been no serious attempts to test it. Then, two years later Jensen burst upon the scene with his indictment of compensatory education programs. In the storm of criticism that followed, McGurk’s research was conveniently forgotten; a virtual conspiracy of silence nullified his data and conclusions. Excellent books on the topic of intelligence and race like those of Baughman and Dahlstrom (1968), Baughman (1971), Miller and Dreger (1973), and Loehlin, Lindzey, and Spuhler (1975) do not contain a single reference to McGurk’s scholarship. Tyler (1965), Shuey (1966), and Jensen (1973) are notable exceptions. Such selective mutism is a remarkable phenomenon in American psychology. Some of us consider it deplorable (Osborne, Noble, & Weyl, 1977).
Recently, however, Dr. McGurk published an important essay up-dating his earlier work and reviewing all the research between 1951 and 1970 on this topic (McGurk, 1975). I shall not spoil your intellectual pleasure by revealing the quantitative detaiIs of that 20-year survey. Suffice it to say that the Culture Hypothesis remains incapable of handling the explanatory burden placed upon it by its advocates. Scientists are indebted to McGurk for initially testing the Klineberg-Montagu idea in an objective manner. Now he has gone beyond this in reviewing the subsequent findings of 80 other investigations. The net score: disconfirmation. Weighted mean Negro overlapping of Caucasian means amounted to only 16%, exactly what would be predicted on the basis of normally-distributed black and white IQs averaging 85 and 100, respectively.
In one critical passage of his Discussion section McGurk (1975, pp. 232-234) clears up some of the confusion about the intelligence test scores of Army recruits collected during mass testing in World War I, as correctly reported by the National Academy of Sciences (Yerkes, 1921). These data (i.e., Alpha, Beta, and Combined Scores) have been widely misrepresented and often erroneously quoted by environmentalists; such as the falsehood that Northern Negroids were of higher average intelligence than Southern Caucasoids in 1917-1919. Regional variations did occur (e. g., the trivial fact that black Alpha medians in the four highest Yankee states were above white Alpha medians in the four lowest Dixie states), but it is not true that the typical scores of Negro soldiers in the North were superior, statistically speaking, to those of white soldiers in the South. Nor was this true of representative military personnel from the two races who were examined with the Army General Classification Test (AGCT) during World War II and the Korean War; nor even of those administered the Armed Forces Qualification Test (AFQT) in the Vietnam War (Jensen, 1973, pp. 60-66; Loehlin, Lindzey, & Spuhler, 1975, pp. 141-145). Quite the contrary, in comparative terms there has been a widening rather than a narrowing of the racial gap in standardized psychological test-score averages over the period covered by our last four major wars. Not only have American blacks not gained in average intelligence since World War I relative to American whites, but also the dramatic rise in blacks’ mean SES since 1918 has failed to produce any significant increment in their absolute IQ levels.
So McGurk (1975) concludes. It is an extremely unpopular conclusion that will be vigorously challenged (as it should be) by the environmentalists. Nevertheless, that appears to be the scientific balance sheet for 60 years of research on the IQs of blacks and whites in the United States. Doughty Frank McGurk, who became a scientific martyr in the prime of his career, has no intention of playing ostrich any longer.
Ashiey-Montagu, M.F. Man’s most dangerous myth: The fallacy of race. (2nd eel.) New York: Columbia University Press, 1945.
Baughman, E.E. Black Americans: A psychological analysis. New York: Academic Press, 1971.
Baughman, E.E., & Dahlstrom, W.G. Negro and white children. New York: Academic Press, 1968.
Jensen, A.R. Educability and group differences. New York: Harper & Row, 1973.
Klineberg, O. Tests of Negro intelligence. In O. Klineberg (Ed.) Characteristics of the American Negro. New York: Harpers, 1944.
Klineberg, O., et al. Does race really make a difference in intelligence? U.S. News and World Report, Oct. 26, 1956, 74-76.
Loehlin, J.e, Lindzey, G., & Spuhler, J.N. Race differences in intelligence. San Francisco: Freeman, 1975.
McCord, W.M., & Demerath, N.J. III. Negro versus white intelligence: A continuing controversy. Harvard Educational Review, 1958, 28, 120-135.
McGurk, F.C.J. The performance of Negro and white high school seniors on cultural and non-cultural psychological test Questions. Washington, D.e: Catholic University, 1951 (microcard).
McGurk, F.C.J. On white and Negro test performance and socio-economic factors. Journal of Abnormal and Social Psychology, 1953, 48, 448-450. (a)
McGurk, F.C.J. Socioeconomic status and culturally-weighted test scores of Negro subjects. Journal of Applied Psychology, 1953, 37, 276-277. (b)
McGurk, F.C.J. A scientist’s report on race differences. U.S. News and World Report, Sept. 21; 1956, 92-96.
McGurk, F.C.J. Fact and prejudice. Contemporary Psychology, 1958, 3, 280.
McGurk, F.C.J. “Negro vs. white intelligence” — an answer. Harvard Educational Review, 1959, 29, 54-62.
McGurk, F.C.J. The culture hypothesis and psychological tests. In R.E. Kuttner (Ed.) Race and modern science. New York: Social: Science Press, 1967.
McGurk, F.C.J. Race differences — twenty years later. Homo, 1975, 26, 219-239.
Miller, K.S., & Dreger, R.M. Comparative studies of blacks and whites in the United States. New York: Seminar Press, 1973.
Osborne, R.T., Noble, C.E., & Weyl, N. (Eds.) Human variation: The biopsychology of age, race, and sex. New York: Academic Press, 1977, in press.
Shuey, A.M. The testing of Negro intelligence. (2nd ed.) New York: Social Science Press, 1966.
Tyler, L.E. The psychology of human differences. (3rd ed.) New York: AppletonCentury-Crofts, 1965.
Yerkes, R.M. Psychological examining in the United States Army. Memoirs of the National Academy of Sciences, 1921, 15.
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Source: Instauration magazine, October 1977