1. Origins of Assessing Intelligence
How do we quantify, or assess intelligence?

2. The History of Assessing Intelligence
Recognition of differences
Plato: “… no two persons are exactly alike; but each differs from the other in natural endowments, one being suited for one occupation and the other for another.”

3. The History of Assessing Intelligence
English scientist Francis Galton was a pioneer in intelligence testing
Cousin of Charles Darwin
Coined the idea of “nature and nurture”
Assess “natural ability” and encourage those of high ability to mate. (Eugenics)

4. The History of Assessing Intelligence
Galton’s assessment included
Reaction time
Sensory acuity
Muscular power
Body proportions
His research didn’t prove that these were related to intelligence.

5. The History of Assessing Intelligence
Alfred Binet was another early intelligence testing pioneer
France passed a mandatory school attendance law
Some students struggled
How to objectively identify students with special needs

6. The History of Assessing Intelligence
Binet & Theodore Simon’s theory
Assume all children follow the same intellectual development
Difference between chronological age and mental age
Chronological
Age
Mental

7. The History of Assessing Intelligence
Binet & Theodore Simon’s theory
Assume all children follow the same intellectual development
Difference between chronological age and mental age
Mental
Age
“Bright”
Chronological
Age

8. The History of Assessing Intelligence
Binet & Theodore Simon’s theory
Assume all children follow the same intellectual development
Difference between chronological age and mental age
Chronological
Age
“Backward”
Mental
Age

9. The History of Assessing Intelligence
Binet’s focus was to identify French school children needing special attention and to improve their education
He feared his tests would
be used to label and limit
opportunities

10. The History of Assessing Intelligence
Lewis Terman of Stanford University found California students didn’t do well with the Paris-developed questions.
He adapted it & created new age norms
Extended upper range to include
“superior adults”
Renamed: Stanford-Benet

11. The History of Assessing Intelligence

12. The History of Assessing Intelligence

13. The History of Assessing Intelligence
For Terman and others like him, intelligence tests revealed the intelligence a person is born with.
German psychologist William Stern came up with a way to quantify the score, calling it Intelligence Quotent.

14. The History of Assessing Intelligence
Mental Age
Chronological Age
IQ =
X 100
An IQ of 100 is considered average
The original IQ formula worked fairly well for children, but not for adults.
Should a 40-year old who does as well as a 20-year old be assigned an IQ of 50?

15. The History of Assessing Intelligence

16. The History of Assessing Intelligence
Terman promoted widespread use of testing and had similar eugenics beliefs as Galton, hoping testing would
“… ultimately result in curtailing the reproduction of feeblemindedness and the elimination of an enormous
amount of crime, pauperism, and industrial inefficiency.”

17. The History of Assessing Intelligence
With Terman’s help, the U.S. government developed tests for newly arriving immigrants and WWI army recruits.
Cultural bias of Anglo-Saxon heritage created problems for many.
(See what I mean with Chitlin’ test)

18. Modern Tests of Mental Ability
You have taken hundreds of tests. Mental ability tests fall into one of two categories:
Achievement Tests: designed to assess what a person has learned
• WAIS • Galileo • AzMerit • SAT
Aptitude Tests: designed to predict a person’s future performance
• ASVAB • Career Aptitude

19. Principles of Test Construction
Psychological tests must meet three criteria:
Standardized: defining uniform test procedures and meaningful scores by comparison with a pretested group
Reliable: the test gives consistent results
Valid: the test measures or predicts what it is supposed to

20. Principles of Test Construction
Example of standardization with the WAIS

21. Principles of Test Construction
Example of standardization with the WAIS

22. Principles of Test Construction
Example of standardization with the WAIS

23. Principles of Test Construction
Example of standardization with the WAIS

24. Principles of Test Construction
Example of standardization with the WAIS

25. Principles of Test Construction
Example of standardization with the WAIS

26. Principles of Test Construction
Example of standardization with the WAIS

27. Principles of Test Construction
Reliability: the test gives consistent results
Test-retest reliability
Split-half reliability
Valid: the test measures or predicts what it is supposed to
Content validity
Predictive validity

28. Assignment
Complete the Frayer vocabulary sheets