1. Wechsler Adult Intelligence Scales
WAIS
Wechsler Adult Intelligence Scales

2. Wechsler Adult Intelligence Scales
David Wechsler devised adult intelligence test (1939)
Now most widely used measure of intelligence for adults and children
IQ is calculated differently
IQ declines as people age

3. Deviation IQ Compare scores to a normative sample of a similar age
Mean = 100, SD = 15
Deviation IQ = (z-score * ) + x
= (z-score * 15) + 100

4. Deviation IQ Average range: 85 to 115 “Gifted” range: 130+
Mentally retarded: < 70
How does that correspond to SD units?

5. WAIS-IV Subtests 11 subtests, with 3 supplementary scales
Full scale IQ
Verbal IQ
Performance IQ
Index Scores
Verbal Comprehension
Perceptual Organizational
Working Memory
Processing Speed

6. Verbal Subtests Vocabulary (VC) Similarities (VC) Information (VC)
Define words
Best measure of G
Similarities (VC)
Tell how two things are alike
Abstract verbal reasoning
Information (VC)
Questions of general knowledge
Crystalized intelligence

7. Verbal Subtests Arithmetic (WM) Digit Span (WM)
Solve arithmetic problems in your head
Working memory, mathematical reasoning
Digit Span (WM)
Repeat a list of numbers forwards and backwards
Working memory

8. Performance Subtests Block Design (PO) Matrix Reasoning (PO)
Make designs using colored cubes
Spatial and nonverbal reasoning
Matrix Reasoning (PO)
Given an incomplete pattern, choose from a number of options how to be complete a picture
Pattern recognition, non-verbal reasoning

9. Performance Subtests Digit Symbol Coding (PS) Paired associates
Each number has a mark put the mark that goes with the number
Processing speed, learning ability or speed of acquisition

10. WAIS-IV Subtests
Each subtest assesses slightly different mental abilities
All a measure of G
Multiple measures that assess multiple abilities provides a comprehensive measure of a person’s intelligence
Highly reliable
Test-retest correlation = .90