Stanford-Binet IQ test

Overview
The development of the Stanford-Binet IQ test initiated the modern field of intelligence testing. The Stanford-Binet itself started with the French psychologist Alfred Binet who was charged by the French government with developing a method of identifying intellectually deficient children for placement in special education programs. As Binet indicated, case studies may be more detailed and at times more helpful, but the time required to test large numbers of people would be huge. Unfortunately, the tests he and his assistant Victor Henri (1892-1940) developed in 1896 were largely disappointing (Fancher, 1985).

Development
Later on, Alfred Binet and physician Theodore Simon collaborated in their work concerning mental retardation in French school children. Between 1905 and 1908, their research at a school for boys in Grange-aux-Belles, France led to the development of the Binet-Simon tests. Employing questions of increasing difficulty, this test measured such things as attention, memory, and verbal skills. Binet cautioned people that these scores should not be taken too literally because of the plasticity of intelligence and the inherent margin of error in the test (Fancher, 1985).

In 1916, Stanford psychologist Lewis Terman released the "Stanford Revision of the Binet-Simon Scale" or the "Stanford-Binet" for short. With the help of several graduate students and validation experiments, he removed several of the Binet-Simon test items and added completely new ones. The test soon became so popular that Robert Yerkes, the president of the American Psychological Association, decided to use the test to develop the Army Alpha and Army Beta tests, which helped classify recruits. Thus, a high-scoring individual would get a grade of A (high officer material), whereas a low-scoring individual would get a grade of E and be rejected (Fancher, 1985).

Present use
Since the Stanford-Binet got its name, it has been revised several times to give us the current Stanford-Binet 5. According to the publisher's website, "The SB5 was normed on a stratified random sample of 4,800 individuals that matches the 2000 U.S. Census. Bias reviews were conducted on all items for gender, ethnic, cultural/religious, regional, and socioeconomic status issues. Validity data was obtained using such instruments as the Stanford-Binet Intelligence Scale, Fourth Edition, the Stanford-Binet Form L-M, the Woodcock-Johnson® III, the Universal Nonverbal Intelligence Test&trade;, the Bender®-Gestalt, the WAIS®-III, the WIAT-II, the WISC-III®, and the WPPSI-R®."

Low variation on individuals tested multiple times indicates the test has high reliability. It features Fluid Reasoning, Knowledge, Quantitative Reasoning, Visual-Spatial Processing, and Working Memory as the five factors tested. Each of these factors is tested in two separate domains, verbal and nonverbal, in order to accurately assess individuals with deafness, limited English, or communication disorders. Examples of test items include verbal analogies to test Verbal Fluid Reasoning and picture absurdities to test Nonverbal Knowledge. In conclusion, the test makers assure people the Stanford-Binet 5 will accurately assess low-end functioning, normal intelligence, and the highest levels of giftedness (Riverside Publishing, 2004).

Students with exceptional scores on this test may be deemed bright, moderately gifted, highly gifted, extremely gifted, or profoundly gifted (contrast these with obsolete terms for low scores. These terms equate with the progressively farther standard deviations their IQ scores are from the mean, bright being 1σ, moderately gifted 2σ, etc. Mensa currently requires a score of 132 on the Stanford-Binet, since the test has a standard deviation of 16, this corresponds to 2σ above the mean in a normalized population.

Criticisms
Despite the recent revision (Stanford-Binet 5), some controversy remains as to the accuracy and bias of this test; however, many psychologists believe the evidence available shows that the Stanford-Binet test is valid, and it remains a popular assessment of intelligence.

As Brown & French point out, "IQ tests serve one function exceptionally well, they predict academic success or failure ... they are composed of items that are representative of the kinds of problems that traditionally dominate school curricula," (1979: 255) and thus only predict that category of school assimilation. Further, "children with the same current status on an IQ test item may vary quite widely in terms of their cognitive potential." (ibid.: 258)

The validity of standardised tests such as Stanford-Binet for testing general intelligence (and indeed the whole concept of general intelligence) has been disputed by a number of commentators. A notable example, though not an intelligence researcher, is Stephen Jay Gould, particularly in his book The Mismeasure of Man. Binet originally devised his test to be carried out one-on-one with an examiner for detecting problem areas, rather than a means of linearly ranking the general intelligence of students.