I. History:
The
Development of Psychological Tests
Psychological tests were
first invented for the purpose of measuring
intelligence. In the early 19th
century there was strong interest in classifying types of mental disabilities.
It was critical to distinguish between mental disabilities and mental
illness.
Sir Francis Galton
proposed the development of measures of central tendency and variability to
summarize data and also developed the concept of correlation.
James McKeen Cattell,
a student of Galton, was the first person to use the term “mental test”.
He developed a set of tests that were able to predict a child’s
scholastic achievement. Cattell’s
goals were related to his desire to strengthen psychology’s scientific
credentials.
Karl Pearson,
also a student of Galton, developed several techniques still used today in
modern statistics, such as the standard deviation and the normal curve.
His most well known statistical concept is the product moment correlation
coefficient, or Pearson’s r.
Alfred Binet
was the first person to formulate a test for children with mental challenges.
He spoke strongly about the nature-nurture controversy, believing that
intelligence could be nurtured, and was not simply the product of nature.
Binet developed cognitive exercises called “mental orthopedics” to
increase the intelligence level of children.
David Wechsler, a student of Pearson, developed two widely used intelligence scales: the Wechsler Adult Intelligence Scales (WAIS) and the Wechsler Intelligence Scale for Children (WISC). Wechsler defined intelligence as, “The global capacity to act purposefully, to think rationally and to deal effectively with the environment.”
Anne Anastasi, one of the best known psychologists in the field of testing, tells us that psychological tests are tools that can be instruments of good or harm, depending on how they are used. She defines a test as an "objective" and "standardized" measure of a sample of behavior.