The Measurement of Intelligence

Abstract

This chapter discusses the Stanford-Binet Intelligence Scale (Binet), the Wechsler Intelligence Scale for Children (WISC), and the Wechsler Adult Intelligence Scale (WAIS). The WISC is essentially a revision and restandardization of Form II of the Wechsler-Bellevue Intelligence Scale and the WAIS bears a similar relationship to Form I of that test. The WISC and the WAIS have a number of features in common. The WISC contains 12 subtests divided into two scales. The WAIS contains 11 subtests also divided into two scales. The composition of the verbal scale is the same as for the WISC; on the performance scale, coding is replaced by digit symbol and mazes are omitted. To find IQ on both the WISC and the WAIS, the raw score on each subtest is first translated to a scaled score with a mean of 10 and an SD of 3. On the WISC, tables for this purpose are provided for ages 5 to 16. On the WAIS, the corresponding table is based on the performance of subjects between the ages of 20 and 34 who generally obtained the highest scores. On both the tests, the sum of the scaled scores on the verbal, performance, and full scales are then converted to IQs with the aid of additional tables.