Lloyd Humphreys
Encyclopedia
Lloyd G. Humphreys was a differential psychologist
and methodologist who focused on assessing individual differences in human behavior
.
His work is among the most widely cited in intelligence research, and he received many prestigious awards in this field. Born in Lorane, Oregon
, Humphreys earned his undergraduate degree at the University of Oregon
in 1935, a master's from Indiana University in 1936, where he first learned about factor analysis
, then received his doctorate at Stanford in 1938, studying under Ernest Hilgard. His dissertation on the partial reinforcement effect (or the Humphreys effect), is considered a classic in the field.
His first position was at Northwestern University
(1939–1945). He was a Carnegie Fellow in Anthropology
(1941–1942, Columbia University
) during that time, then taught at the University of Washington
(1946–1948) and Stanford (1948–1952). He then took a post as Research Director, Personnel Laboratory, for the United States Air Force
(1951–1957). He then spent the remainder of his career at the University of Illinois at Urbana-Champaign
(1957–1984).
Humphreys argued that much psychological research fails to replicate because of inadequate sample size
s, because correlations fluctuate when Ns are small. His own empirical research typically involved large-scale longitudinal studies such as Project Talent
.
In the 1970s, Humphreys chaired the American Psychological Association
's Task Force on ability and achievement testing. He deemed a general intelligence test ‘‘the single most important test that can be administered for vocational guidance purposes’’ (Humphreys, 1985, p. 211). He also coined the concept "inadequate learning syndrome" (ILS) and argued it was a more important social problem than the AIDS epidemic (Humphreys, 1988).
Amid the controversy generated by publication of The Bell Curve
in 1994, Humphreys wrote a target article (Humphreys, 1994), which stimulated a series of comments by a number of prominent scholars in the field. He generated further controversy by accepting funding from the Pioneer Fund
. He was also one of 52 signatories on "Mainstream Science on Intelligence
," an editorial written by Linda Gottfredson
and published in the Wall Street Journal, which defended the findings on intelligence
in The Bell Curve
.
Psychology
Psychology is the study of the mind and behavior. Its immediate goal is to understand individuals and groups by both establishing general principles and researching specific cases. For many, the ultimate goal of psychology is to benefit society...
and methodologist who focused on assessing individual differences in human behavior
Human behavior
Human behavior refers to the range of behaviors exhibited by humans and which are influenced by culture, attitudes, emotions, values, ethics, authority, rapport, hypnosis, persuasion, coercion and/or genetics....
.
His work is among the most widely cited in intelligence research, and he received many prestigious awards in this field. Born in Lorane, Oregon
Lorane, Oregon
Lorane is an unincorporated community in Lane County, Oregon, United States. It is located on Territorial Road about 20 miles southwest of Eugene; it is 13 miles northwest of Cottage Grove. The community is near the headwaters of the North Fork Siuslaw River in a valley in the foothills of the...
, Humphreys earned his undergraduate degree at the University of Oregon
University of Oregon
-Colleges and schools:The University of Oregon is organized into eight schools and colleges—six professional schools and colleges, an Arts and Sciences College and an Honors College.- School of Architecture and Allied Arts :...
in 1935, a master's from Indiana University in 1936, where he first learned about factor analysis
Factor analysis
Factor analysis is a statistical method used to describe variability among observed, correlated variables in terms of a potentially lower number of unobserved, uncorrelated variables called factors. In other words, it is possible, for example, that variations in three or four observed variables...
, then received his doctorate at Stanford in 1938, studying under Ernest Hilgard. His dissertation on the partial reinforcement effect (or the Humphreys effect), is considered a classic in the field.
His first position was at Northwestern University
Northwestern University
Northwestern University is a private research university in Evanston and Chicago, Illinois, USA. Northwestern has eleven undergraduate, graduate, and professional schools offering 124 undergraduate degrees and 145 graduate and professional degrees....
(1939–1945). He was a Carnegie Fellow in Anthropology
Anthropology
Anthropology is the study of humanity. It has origins in the humanities, the natural sciences, and the social sciences. The term "anthropology" is from the Greek anthrōpos , "man", understood to mean mankind or humanity, and -logia , "discourse" or "study", and was first used in 1501 by German...
(1941–1942, Columbia University
Columbia University
Columbia University in the City of New York is a private, Ivy League university in Manhattan, New York City. Columbia is the oldest institution of higher learning in the state of New York, the fifth oldest in the United States, and one of the country's nine Colonial Colleges founded before the...
) during that time, then taught at the University of Washington
University of Washington
University of Washington is a public research university, founded in 1861 in Seattle, Washington, United States. The UW is the largest university in the Northwest and the oldest public university on the West Coast. The university has three campuses, with its largest campus in the University...
(1946–1948) and Stanford (1948–1952). He then took a post as Research Director, Personnel Laboratory, for the United States Air Force
United States Air Force
The United States Air Force is the aerial warfare service branch of the United States Armed Forces and one of the American uniformed services. Initially part of the United States Army, the USAF was formed as a separate branch of the military on September 18, 1947 under the National Security Act of...
(1951–1957). He then spent the remainder of his career at the University of Illinois at Urbana-Champaign
University of Illinois at Urbana-Champaign
The University of Illinois at Urbana–Champaign is a large public research-intensive university in the state of Illinois, United States. It is the flagship campus of the University of Illinois system...
(1957–1984).
Humphreys argued that much psychological research fails to replicate because of inadequate sample size
Sample size
Sample size determination is the act of choosing the number of observations to include in a statistical sample. The sample size is an important feature of any empirical study in which the goal is to make inferences about a population from a sample...
s, because correlations fluctuate when Ns are small. His own empirical research typically involved large-scale longitudinal studies such as Project Talent
Project Talent
Project Talent was a large-scale, national survey of the abilities, aptitudes, inclinations, quality of life, and backgrounds of over 400,000 U.S. high school students undertaken in 1960...
.
In the 1970s, Humphreys chaired the American Psychological Association
American Psychological Association
The American Psychological Association is the largest scientific and professional organization of psychologists in the United States. It is the world's largest association of psychologists with around 154,000 members including scientists, educators, clinicians, consultants and students. The APA...
's Task Force on ability and achievement testing. He deemed a general intelligence test ‘‘the single most important test that can be administered for vocational guidance purposes’’ (Humphreys, 1985, p. 211). He also coined the concept "inadequate learning syndrome" (ILS) and argued it was a more important social problem than the AIDS epidemic (Humphreys, 1988).
Amid the controversy generated by publication of The Bell Curve
The Bell Curve
The Bell Curve is a best-selling and controversial 1994 book by the Harvard psychologist Richard J. Herrnstein and political scientist Charles Murray...
in 1994, Humphreys wrote a target article (Humphreys, 1994), which stimulated a series of comments by a number of prominent scholars in the field. He generated further controversy by accepting funding from the Pioneer Fund
Pioneer Fund
The Pioneer Fund is an American non-profit foundation established in 1937 "to advance the scientific study of heredity and human differences." Currently headed by psychology professor J. Philippe Rushton, the fund states that it focuses on projects it perceives will not be easily funded due to...
. He was also one of 52 signatories on "Mainstream Science on Intelligence
Mainstream Science on Intelligence
Mainstream Science on Intelligence was a public statement issued by a group of academic researchers in fields allied to intelligence testing that claimed to present those findings widely accepted in the expert community...
," an editorial written by Linda Gottfredson
Linda Gottfredson
Linda Susanne Gottfredson is a professor of educational psychology at the University of Delaware and co-director of the Delaware-Johns Hopkins Project for the Study of Intelligence and Society. Gottfredson's work has been influential in shaping U.S...
and published in the Wall Street Journal, which defended the findings on intelligence
Intelligence
Intelligence has been defined in different ways, including the abilities for abstract thought, understanding, communication, reasoning, learning, planning, emotional intelligence and problem solving....
in The Bell Curve
The Bell Curve
The Bell Curve is a best-selling and controversial 1994 book by the Harvard psychologist Richard J. Herrnstein and political scientist Charles Murray...
.
Selected works
- Humphreys LG (1939). The effect of random alternation of reinforcement on the acquisition and extinction of conditioned eyelid reactions. Journal of Experimental Psychology, 25, 141–158.
- Humphreys, L. G. (1985). General intelligence: An integration of factor, test, and simplex theory. In B. B. Wolman (Ed.), Handbook of intelligence ( pp. 201–224). New York: Wiley.
- Humphreys, L. G. (1988). Trends in levels of academic achievement of blacks and other minorities. Intelligence, 12, 231–260.
- Humphreys, L. G. (1994). Intelligence from the standpoint of a (pragmatic) behaviorist. Psychological Inquiry, 5, 179–192.