Louis Leon Thurstone

Infobox_Scientist
name = Louis Leon Thurstone


caption = Louis Leon Thurstone
birth_date = birth date|1887|5|29|mf=y birth_place = Chicago, Illinios
nationality =
death_date = death date and age|1955|9|30|1887|5|29|mf=y
field = Psychometrics
work_institution = University of Chicago University of North Carolina
alma_mater = Cornell University and University of Chicago
doctoral_advisor = James Angell
doctoral_students = Paul Horst
Calvin Taylor
Ledyard R Tucker
Thelma Thurstone
Harold Gulliksen
known_for = Multiple Factor Analysis
Intelligence testing
Law of Comparative Judgment

Louis Leon Thurstone (29 May 1887–30 September 1955) was a U.S. pioneer in the fields of psychometrics and psychophysics. He conceived the approach to measurement known as the law of comparative judgment, and is well known for his contributions to factor analysis.

Background and history

Thurstone originally received a masters in Mechanical Engineering from Cornell University in 1912, before undertaking a PhD in Psychology at the University of Chicago, which he completed in 1917. He later returned to that university, and he taught and conducted research there between 1924 and 1952. He is responsible for the standardized mean and standard deviation of IQ scores used today, as opposed to the Intelligence Test system originally used by Alfred Binet. He is also known for the development of the Thurstone scale [Citation
last =Horst
first =Paul
author-link =
last2 =
first2 =
author2-link =
title =L. L. Thurstone and the Science of Human Behavior
journal =Science
volume =122
issue =3183
pages =1259-1260
date =1955-12-30
year =1955
url =http://www.sciencemag.org/cgi/reprint/122/3183/1259.pdf?ck=nck
doi =
id = ] .

Thurstone was also an environmentalist, and suggested an early system for generating hydroelectric power from rivers and waterfalls.

Factor analysis and work on intelligence

Thurstone's work in factor analysis led him to formulate a model of intelligence center around "Primary Mental Abilities" (PMAs), which were independent group factors of intelligence that different individuals possessed in varying degrees. He opposed the notion of a singular general intelligence that factored into the scores of all psychometric tests and was expressed as a mental age. This idea was unpopular at the time due to its obvious conflicts with Spearman's "mental energy" model, and is today still largely discredited. Nonetheless, Thurstone's contributions to methods of factor analysis have proved invaluable in establishing and verifying later psychometric factor structures, and has influenced the hierarchical models of intelligence in use in intelligence tests such as WAIS and the modern Stanford-Binet IQ test.

The seven primary mental abilities in Thurstone's model were "verbal comprehension", "word fluency", "number facility", "spatial visualization", "associative memory", "perceptual speed" and "reasoning".

Contributions to measurement

Despite his contributions to factor analysis, Thurstone (1959, p. 267) cautioned: "When a problem is so involved that no rational formulation is available, then some quantification is still possible by the coefficients of correlation of contingency and the like. But such statistical procedures constitute an acknowledgement of failure to rationalize the problem and to establish functions that underlie the data. We want to measure the separation between the two opinions on the attitude continuum and we want to test the validity of the assumed continuum by means of its internal consistency". Thurstone's approach to measurement was termed the law of comparative judgment. He applied the approach in psychophysics, and later to the measurement of psychological values. The so-called 'Law', which can be regarded as a measurement model, involves subjects making a comparison between each of a number of pairs of stimuli with respect to magnitude of a property, attribute, or attitude. Methods based on the approach to measurement can be used to estimate such scale values.

Thurstone's Law of comparative judgment has important links to modern approaches to social and psychological measurement. In particular, the approach bears a close conceptual relation to the Rasch model (Andrich, 1978), although Thurstone typically employed the normal distribution in applications of the Law of comparative judgment whereas the Rasch model is a simple logistic function. Thurstone anticipated a key epistemological requirement of measurement later articulated by Rasch, which is that relative scale locations must 'transcend' the group measured; i.e. scale locations must be invariant to (or independent of) the particular group of persons instrumental to comparisons between the stimuli. Thurstone (1929) also articulated what he referred to as the "additivity criterion" for scale differences, a criterion which must be satisfied in order to obtain interval-level measurements.

Footnotes

References

*Citation
id = PMID:11625304
url= http://www.ncbi.nlm.nih.gov/pubmed/11625304
last=Martin
first=O
publication-date=1997
year=1997
title= [Psychological measurement from Binet to Thurstone, (1900-1930)]
volume=
issue=4
periodical=Revue de synthèse / Centre international de synthèse
pages=457-93
*Citation
id = PMID:3322058
url= http://www.ncbi.nlm.nih.gov/pubmed/3322058
last=Thurstone
first=L L
publication-date=
year=
title=Psychophysical analysis. By L. L. Thurstone, 1927.
volume=100
issue=3-4
periodical=The American journal of psychology
pages=587-609
*Citation
id = PMID:4881041
url= http://www.ncbi.nlm.nih.gov/pubmed/4881041
last=Gulliksen
first=H
publication-date=1968 Nov
year=1968
title=Louis Leon Thurstone, experimental and mathematical psychologist.
volume=23
issue=11
periodical=The American psychologist
pages=786-802
*Citation
id = PMID:13302517
url= http://www.ncbi.nlm.nih.gov/pubmed/13302517
last=WOLFLE
first=D
publication-date=1956 Mar
year=1956
title=Louis Leon Thurstone, 1887-1955.
volume=69
issue=1
periodical=The American journal of psychology
pages=131-4
*Citation
id = PMID:13274085
url= http://www.ncbi.nlm.nih.gov/pubmed/13274085
last=HORST
first=P
publication-date=1955 Dec 30
year=1955
title=L.L. Thurstone and the science of human behavior.
volume=122
issue=3183
periodical=Science
pages=1259-60
*Andrich, D. (1978b). "Relationships between the Thurstone and Rasch approaches to item scaling". Applied Psychological Measurement, 2, 449-460.

*Thurstone, L.L. (1927). "A law of comparative judgement". Psychological Review, 34, 278-286.

*Thurstone, L.L. (1929). "The Measurement of Psychological Value". In TV. Smith and W.K. Wright (Eds.), Essays in Philosophy by Seventeen Doctors of Philosophy of the University of Chicago. Chicago: Open Court.

*Thurstone, L.L. (1959). "The Measurement of Values". Chicago: The University of Chicago Press.

External links

* [http://psychclassics.yorku.ca/Thurstone/ The Vectors of Mind 1934]
* [http://www.indiana.edu/~intell/lthurstone.shtml Human intelligence: Thurstone]
* [http://www.psych.usyd.edu.au/difference5/scholars/thurstone.html Biographical information]
* [http://www.unc.edu/depts/quantpsy/thurstone/history.htm History of Thurstone's psychometric lab]

Persondata
NAME= Thurstone, Louis Leon
ALTERNATIVE NAMES=
SHORT DESCRIPTION= American scientist
DATE OF BIRTH= May 29, 1887
PLACE OF BIRTH=
DATE OF DEATH= September 29, 1955
PLACE OF DEATH=