Charles Spearman
Encyclopedia
Charles Edward Spearman, FRS (10 September 1863 - 17 September 1945) was an English
psychologist
known for work in statistics
, as a pioneer of factor analysis
, and for Spearman's rank correlation coefficient
. He also did seminal work on models for human intelligence, including his theory that disparate cognitive test scores reflect a single general factor
and coining the term g factor.
he resigned to study for a PhD in experimental psychology. In Britain, psychology was generally seen as a branch of philosophy
and Spearman chose to study in Leipzig
under Wilhelm Wundt
, because Spearman had no conventional qualifications and Leipzig had liberal entrance requirements. He started in 1897, and after some interruption (he was recalled to the army during the South African War) he obtained his degree in 1906. He had already published his seminal paper on the factor analysis of intelligence (1904). Spearman met and impressed the psychologist William McDougall
who arranged for Spearman to replace him when he left his position at University College London
. Spearman stayed at University College until he retired in 1931. Initially he was Reader and head of the small psychological laboratory. In 1911 he was promoted to the Grote professorship of the Philosophy of Mind and Logic
. His title changed to Professor of Psychology in 1928 when a separate Department of Psychology was created.
When Spearman was elected to the Royal Society
in 1924 the citation read "Dr. Spearman has made many researches in experimental psychology. His many published papers cover a wide field, but he is especially distinguished by his pioneer work in the application of mathematical methods to the analysis of the human mind, and his original studies of correlation in this sphere. He has inspired and directed research work by many pupils."
Chief amongst these achievements was the discovery of the general factor in human intelligence (Spearman, 1904),
and his subsequent development of a theory of "g" (Spearman, 1923)
and synthesis of empirical work on ability (Spearman, 1927)
.
Spearman was strongly influenced by the work of Francis Galton
. Galton did pioneering work in psychology and developed correlation
, the main statistical tool used by Spearman.
In statistics, Spearman developed rank correlation
(1904), a non-parametric version of the conventional Pearson correlation, as well as both the widely used correction for attenuation
(1907), and the earliest version of a 'factor analysis (Lovie & Lovie, 1996, p. 81)
. His statistical work was not appreciated by his University College colleague Karl Pearson
and there was a long feud between them.
Although Spearman achieved most recognition in his day for his statistical work, he regarded this work as subordinate to his quest for the fundamental laws of psychology, and he is now similarly renowned for both.
and Edward Thorndike
) was made in the course of the Andrew Carnegie
sponsored International Examinations Inquiry Meetings
.
Here, Spearman gives a compact summary of his findings and theory of g:
As time progressed, Spearman increasingly argued that g was not, from a psychological point of view, a single ability but composed of two very different abilities which normally worked closely together. These he called "eductive" ability and "reproductive" ability. The former term comes from the Latin root "educere" - which means to "draw out" and thus refers to the ability to make meaning out of confusion. He claimed that to understand these different abilities "in their trenchent contrast, their ubiquitous cooperation, and their genetic interlinkage" would, for the study of "individual differences - and even cognition itself" - be "the very beginning of wisdom.".
Despite Spearman arguing that g was what emerged from a large battery of tests, i.e., that it was not measured perfectly by any single test, the fact that g-theory suggested that much of ability could be captured in a single factor, and his suggestion that "the education of relations and correlates" underlay this general factor led to the quest for tests of this general ability. Raven's Progressive Matrices
might be regarded as one of these although Raven himself clearly stated that his tests should not be regarded as "intelligence" tests.
While arguing consistently that g accounted for much of individual differences in "ability" (as measured by tests which had "no place in schools), Spearman also acknowledged that "Every normal man, woman, and child is … a genius at something … It remains to discover at what …" He thought that detecting these areas of genius required procedures very different from "any of the testing procedures at present in current usage", though he felt these to be capable of "vast improvement".
While, like Arthur Jensen
after him, Spearman felt that though g could be detected in any broad set of cognitive measures, he felt that the tests from which his g had emerged "had no place in schools" because they "deflected" teachers', pupils', parents' and politicians' attention from the business of education which, as the Latin root of the word implies, should be concerned with "drawing out" whatever talents a student may have .
Spearman's model was influential, but was also critiqued by many authors, such as, for instance Godfrey Thomson
. In particular the move from a psychological g to a biological g – that is a unitary biological mechanism or mechanisms has remained a matter of active research.
is a statistical test that is used to find relationships between multiple correlated measures and Spearman played a clear part in its development. Spearman coined the term factor analysis and used it extensively in analysing multiple measures of cognitive performance. It was factor analytic data which lead Spearman to postulate his original general and specific factor models of ability. Factor analysis and its modern relations confirmatory factor analysis
and structural equation modelling underlie much of modern behaviour research.
There is an account of Spearman's main achievements in
There is a photograph of Spearman at
England
England is a country that is part of the United Kingdom. It shares land borders with Scotland to the north and Wales to the west; the Irish Sea is to the north west, the Celtic Sea to the south west, with the North Sea to the east and the English Channel to the south separating it from continental...
psychologist
Psychologist
Psychologist is a professional or academic title used by individuals who are either:* Clinical professionals who work with patients in a variety of therapeutic contexts .* Scientists conducting psychological research or teaching psychology in a college...
known for work in statistics
Statistics
Statistics is the study of the collection, organization, analysis, and interpretation of data. It deals with all aspects of this, including the planning of data collection in terms of the design of surveys and experiments....
, as a pioneer of 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...
, and for Spearman's rank correlation coefficient
Spearman's rank correlation coefficient
In statistics, Spearman's rank correlation coefficient or Spearman's rho, named after Charles Spearman and often denoted by the Greek letter \rho or as r_s, is a non-parametric measure of statistical dependence between two variables. It assesses how well the relationship between two variables can...
. He also did seminal work on models for human intelligence, including his theory that disparate cognitive test scores reflect a single general factor
General intelligence factor
The g factor, where g stands for general intelligence, is a statistic used in psychometrics to model the mental ability underlying results of various tests of cognitive ability...
and coining the term g factor.
Biography
Spearman had an unusual background for a psychologist. After 15 years as an officer in the British ArmyBritish Army
The British Army is the land warfare branch of Her Majesty's Armed Forces in the United Kingdom. It came into being with the unification of the Kingdom of England and Scotland into the Kingdom of Great Britain in 1707. The new British Army incorporated Regiments that had already existed in England...
he resigned to study for a PhD in experimental psychology. In Britain, psychology was generally seen as a branch of philosophy
Philosophy
Philosophy is the study of general and fundamental problems, such as those connected with existence, knowledge, values, reason, mind, and language. Philosophy is distinguished from other ways of addressing such problems by its critical, generally systematic approach and its reliance on rational...
and Spearman chose to study in Leipzig
University of Leipzig
The University of Leipzig , located in Leipzig in the Free State of Saxony, Germany, is one of the oldest universities in the world and the second-oldest university in Germany...
under Wilhelm Wundt
Wilhelm Wundt
Wilhelm Maximilian Wundt was a German physician, psychologist, physiologist, philosopher, and professor, known today as one of the founding figures of modern psychology. He is widely regarded as the "father of experimental psychology"...
, because Spearman had no conventional qualifications and Leipzig had liberal entrance requirements. He started in 1897, and after some interruption (he was recalled to the army during the South African War) he obtained his degree in 1906. He had already published his seminal paper on the factor analysis of intelligence (1904). Spearman met and impressed the psychologist William McDougall
William McDougall (psychologist)
William McDougall FRS was an early twentieth century psychologist who spent the first part of his career in the United Kingdom and the latter part in the United States...
who arranged for Spearman to replace him when he left his position at University College London
University College London
University College London is a public research university located in London, United Kingdom and the oldest and largest constituent college of the federal University of London...
. Spearman stayed at University College until he retired in 1931. Initially he was Reader and head of the small psychological laboratory. In 1911 he was promoted to the Grote professorship of the Philosophy of Mind and Logic
Grote Chair of the Philosophy of Mind and Logic
The Grote Chair of the Philosophy of Mind and Logic is an endowed chair at University College London.-Origin:Along with Moral Philosophy, Philosophy of Mind and Logic was one of two Philosophy chairs established at the founding of University College London...
. His title changed to Professor of Psychology in 1928 when a separate Department of Psychology was created.
When Spearman was elected to the Royal Society
Royal Society
The Royal Society of London for Improving Natural Knowledge, known simply as the Royal Society, is a learned society for science, and is possibly the oldest such society in existence. Founded in November 1660, it was granted a Royal Charter by King Charles II as the "Royal Society of London"...
in 1924 the citation read "Dr. Spearman has made many researches in experimental psychology. His many published papers cover a wide field, but he is especially distinguished by his pioneer work in the application of mathematical methods to the analysis of the human mind, and his original studies of correlation in this sphere. He has inspired and directed research work by many pupils."
Chief amongst these achievements was the discovery of the general factor in human intelligence (Spearman, 1904),
and his subsequent development of a theory of "g" (Spearman, 1923)
and synthesis of empirical work on ability (Spearman, 1927)
.
Spearman was strongly influenced by the work of Francis Galton
Francis Galton
Sir Francis Galton /ˈfrɑːnsɪs ˈgɔːltn̩/ FRS , cousin of Douglas Strutt Galton, half-cousin of Charles Darwin, was an English Victorian polymath: anthropologist, eugenicist, tropical explorer, geographer, inventor, meteorologist, proto-geneticist, psychometrician, and statistician...
. Galton did pioneering work in psychology and developed correlation
Correlation
In statistics, dependence refers to any statistical relationship between two random variables or two sets of data. Correlation refers to any of a broad class of statistical relationships involving dependence....
, the main statistical tool used by Spearman.
In statistics, Spearman developed rank correlation
Spearman's rank correlation coefficient
In statistics, Spearman's rank correlation coefficient or Spearman's rho, named after Charles Spearman and often denoted by the Greek letter \rho or as r_s, is a non-parametric measure of statistical dependence between two variables. It assesses how well the relationship between two variables can...
(1904), a non-parametric version of the conventional Pearson correlation, as well as both the widely used correction for attenuation
Correction for attenuation
Correction for attenuation is a statistical procedure, due to Spearman , to "rid a correlation coefficient from the weakening effect of measurement error" , a phenomenon also known as regression dilution. In measurement and statistics, it is also called disattenuation...
(1907), and the earliest version of a 'factor analysis (Lovie & Lovie, 1996, p. 81)
. His statistical work was not appreciated by his University College colleague Karl Pearson
Karl Pearson
Karl Pearson FRS was an influential English mathematician who has been credited for establishing the disciplineof mathematical statistics....
and there was a long feud between them.
Although Spearman achieved most recognition in his day for his statistical work, he regarded this work as subordinate to his quest for the fundamental laws of psychology, and he is now similarly renowned for both.
Theory of intelligence
A wonderful record of Spearman's views on g (and also those of Godfrey ThomsonGodfrey Thomson
Sir Godfrey Hilton Thomson was an English educational psychologist known as a critical pioneer in intelligence research.He worked at Armstrong College, Newcastle upon Tyne from 1906 to 1925, before moving to theUniversity of Edinburgh from 1925 until 1951, where he was the Bell Professor of...
and Edward Thorndike
Edward Thorndike
Edward Lee "Ted" Thorndike was an American psychologist who spent nearly his entire career at Teachers College, Columbia University. His work on animal behavior and the learning process led to the theory of connectionism and helped lay the scientific foundation for modern educational psychology...
) was made in the course of the Andrew Carnegie
Carnegie
Carnegie may refer to:*Andrew Carnegie, Scottish-American industrialist and philanthropist, for whom many entries on this page are named*Dale Carnegie, motivational speaker and author*David Carnegie , Scottish-Swedish industrialist...
sponsored International Examinations Inquiry Meetings
.
Here, Spearman gives a compact summary of his findings and theory of g:
- When asked what G is, one has to distinguish between the meanings of terms and the facts about things. G means a particular quantity derived from statistical operations. Under certain conditions the score of a person at a mental test can be divided into two factors, one of which is always the same in all tests, whereas the other varies from one test to another; the former is called the general factor or G, while the other is called the specific factor. This then is what the G term means, a score-factor and nothing more. But this meaning is sufficient to render the term well defined so that the underlying thing is susceptible to scientific investigation; we can proceed to find out facts about this score-factor, or G. We can ascertain the kind of mental operations in which it plays a dominant part as compared with the other or specific factor. And so the discovery has been made that G is dominant in such operations as reasoning, or learning Latin; whereas it plays a very small part indeed in such operation (sic) as distinguishing one tone from another. . . G tends to dominate according as the performance involves the perceiving of relations, or as it requires that relations seen in one situation should be transferred to another. . . . On weighing the evidence, many of us used to say that this G appears to measure some form of mental energy. But in the first place, such a suggestion is apt to invite needless controversy. This can be avoided by saying more cautiously that G behaves as if it measured an energy. In the second place, however, there seems to be good reason for changing the concept of energy to that of "power" (which, of course, is energy or work divided by time). In this way, one can talk about mind power in much the same manner as about horse power. . . . . . .G is in the normal course of events determined innately; a person can no more be trained to have it in higher degree than he can be trained to be taller. (pp. 156 –157).
As time progressed, Spearman increasingly argued that g was not, from a psychological point of view, a single ability but composed of two very different abilities which normally worked closely together. These he called "eductive" ability and "reproductive" ability. The former term comes from the Latin root "educere" - which means to "draw out" and thus refers to the ability to make meaning out of confusion. He claimed that to understand these different abilities "in their trenchent contrast, their ubiquitous cooperation, and their genetic interlinkage" would, for the study of "individual differences - and even cognition itself" - be "the very beginning of wisdom.".
Despite Spearman arguing that g was what emerged from a large battery of tests, i.e., that it was not measured perfectly by any single test, the fact that g-theory suggested that much of ability could be captured in a single factor, and his suggestion that "the education of relations and correlates" underlay this general factor led to the quest for tests of this general ability. Raven's Progressive Matrices
Raven's Progressive Matrices
Raven's Progressive Matrices are non-verbal multiple choice measures of the reasoning component of Spearman's g , which is often referred to as general intelligence. The tests were originally developed by John C. Raven in 1936...
might be regarded as one of these although Raven himself clearly stated that his tests should not be regarded as "intelligence" tests.
While arguing consistently that g accounted for much of individual differences in "ability" (as measured by tests which had "no place in schools), Spearman also acknowledged that "Every normal man, woman, and child is … a genius at something … It remains to discover at what …" He thought that detecting these areas of genius required procedures very different from "any of the testing procedures at present in current usage", though he felt these to be capable of "vast improvement".
While, like Arthur Jensen
Arthur Jensen
Arthur Robert Jensen is a Professor Emeritus of educational psychology at the University of California, Berkeley. Jensen is known for his work in psychometrics and differential psychology, which is concerned with how and why individuals differ behaviorally from one another.He is a major proponent...
after him, Spearman felt that though g could be detected in any broad set of cognitive measures, he felt that the tests from which his g had emerged "had no place in schools" because they "deflected" teachers', pupils', parents' and politicians' attention from the business of education which, as the Latin root of the word implies, should be concerned with "drawing out" whatever talents a student may have .
Spearman's model was influential, but was also critiqued by many authors, such as, for instance Godfrey Thomson
Godfrey Thomson
Sir Godfrey Hilton Thomson was an English educational psychologist known as a critical pioneer in intelligence research.He worked at Armstrong College, Newcastle upon Tyne from 1906 to 1925, before moving to theUniversity of Edinburgh from 1925 until 1951, where he was the Bell Professor of...
. In particular the move from a psychological g to a biological g – that is a unitary biological mechanism or mechanisms has remained a matter of active research.
Factor analysis
Factor analysisFactor 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...
is a statistical test that is used to find relationships between multiple correlated measures and Spearman played a clear part in its development. Spearman coined the term factor analysis and used it extensively in analysing multiple measures of cognitive performance. It was factor analytic data which lead Spearman to postulate his original general and specific factor models of ability. Factor analysis and its modern relations confirmatory factor analysis
Confirmatory factor analysis
In statistics, confirmatory factor analysis is a special form of factor analysis. It is used to test whether measures of a construct are consistent with a researcher's understanding of the nature of that construct . In contrast to exploratory factor analysis, where all loadings are free to vary,...
and structural equation modelling underlie much of modern behaviour research.
Works
- "General Intelligence," objectively determined and measured. "American Journal of Psychology" 1904
- Proof and measurement of association between two things. "American Journal of Psychology" 1904
- Demonstration of Formulae for True Measurement of Correlation. "American Journal of Psychology" 1907
Biographies of Spearman
- Lovie, P and Lovie A. D. (1996) Charles Edward Spearman F.R.S. (1863–1945) Notes and Records of the Royal Society of London, 50, 1-14.
- Lovie, P (1997) Spearman, Charles Edward pp. 342–3 in Leading Personalities in Statistical Sciences from the Seventeenth Century to the Present, (ed. N. L. Johnson and S. Kotz) 1997. New York: Wiley. Originally published in Encyclopedia of Statistical Science.
External links
Spearman's 1904 General Intelligence paper is available on the Classics in the History of Psychology website.There is an account of Spearman's main achievements in
There is a photograph of Spearman at
- Charles Spearman on the Portraits of Statisticians page.
