Charles Spearman was well known as the pioneer of factor analysis as a statistical technique to reduce and interpret data. He was the first psychologist who used the application of mathematical models for analyzing and interpreting the complexities present in human mind. He was an English psychologist who gave the concept of General intelligence or more commonly g factor through which he defined intelligence as a cognitive ability which can be measured and expressed numerically. Using the technique of factor analysis, he conducted a study to prove this theory through which he observed and inferred that people with higher intelligence levels did well on series of mental aptitude tests whereas people with lower intelligence did not perform well enough on all these tests. His most famous statistical invention Spearman’s rank correlation coefficient is used to measure statistical dependence between two variables.
Born in London, United Kingdom on 10th September 1863 he showed an unusual talent and ability of becoming a psychologist from childhood. He started off his career by joining the British army. After serving the British army for 15 years he resigned to study for a PhD in experimental psychology. Since Spearman had no previous required qualifications for the degree of his choice he decided to study at University of Leipzig, Germany, which had liberal entrance policies, under the supervision of Wilhelm Wundt. Spearman’s numerous achievements also include his association as a professor of mind and logic in place of William McDougall at University College, London. Mcdougall got so impressed by the aptitude and capabilities of Spearman that he recommended him to teach at University College, London as a substitute for him. Spearman stayed and taught at University College, London until he retired in 1931. He obtained the entitlement of professor of psychology in 1928 when a separate department of psychology was created at the university.
His most influential g factor theory served as a stepping stone for intelligence theories. He identified g as a specific quantity which came out as an outcome of statistical operations. He also divided the intelligence score of a person into two categories, the one which remains constant over the period of time termed as general factor or g whereas the other which changes from time to time classified as specific factor. He also proposed that g factor is composed of two different capabilities that are related to each other very closely. He identified these two abilities as “eductive” and “reproductive” ability. There was another factor observed by Charles Spearman in assessing intelligence which he named as special factor. Individuals who scored higher on tests persistently possessed the special factor in intelligence.
Charles Spearman’s works were influenced by Hans Eysenck, Philip Vernon, Cyril Burt and Arthur Jensen but the strongest influences on his work were from Francis Galton who first developed correlation as a statistical tool in psychology. His notable accomplishments also included becoming the fellow member of the Royal society in London. Spearman breathed his last on 17th September, 1945 in London, United Kingdom.