The psychometric approach to intelligence emphasizes people’s
performance on standardized aptitude tests. Aptitude tests predict
people’s future ability to acquire skills or knowledge. Achievement
tests, on the other hand, measure skills and knowledge that people have
already learned.
Types of Tests
Intelligence tests can be given individually or to groups of people. The
best-known individual intelligence tests are the Binet-Simon scale, the
Stanford-Binet Intelligence Scale, and the Wechsler Adult Intelligence Scale.
The Binet-Simon Scale
Alfred Binet and his colleague Theodore Simon devised
this general test of mental ability in 1905, and it was revised in 1908 and
1911. The test yielded scores in terms of mental age. Mental
age is the chronological age that typically corresponds to a
particular level of performance.
Example: A ten-year-old child whose score indicates a mental
age of twelve performed like a typical
twelve-year-old.
The Stanford-Binet Intelligence Scale
In 1916, Lewis Terman and his colleagues at
Stanford University created the Stanford-Binet Intelligence Scale by
expanding and revising the Binet-Simon scale. The Stanford-Binet yielded
scores in terms of intelligence quotients. The intelligence
quotient (IQ) is the mental age divided by the chronological
age and multiplied by 100. IQ scores allowed children of different ages
to be compared.
Example: A ten-year-old whose performance resembles that of
a typical twelve-year-old has an IQ of 120 (12 divided by 10
times 100).
