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

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.”

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)

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.

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

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

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

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

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

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

The History of Assessing Intelligence

The History of Assessing Intelligence

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.

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?

The History of Assessing Intelligence

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.”

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)

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

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

Principles of Test Construction Example of standardization with the WAIS

Principles of Test Construction Example of standardization with the WAIS

Principles of Test Construction Example of standardization with the WAIS

Principles of Test Construction Example of standardization with the WAIS

Principles of Test Construction Example of standardization with the WAIS

Principles of Test Construction Example of standardization with the WAIS

Principles of Test Construction Example of standardization with the WAIS

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

Assignment Complete the Frayer vocabulary sheets