DEVELOPMENT OF INTELLIGENCE TESTS Psychological Testing Unit

TEST DEVELOPMENT  In 1904 a Paris based psychologist was asked to design a test to pick out “slow learners.”  Alfred Binet: could not define intelligence but believed it increased with age  He would ask children questions and determine at what age children would be able to answer  Binet made the first of what we today call “IQ” tests

STANFORD-BINET INTELLIGENCE SCALE  Created at Vanderbilt University  A revision of Binet’s original test  Currently used in the United States to measure IQ  Mainly given to school aged children  Students asked to define words and explain events in daily life

INTELLIGENCE QUOTIENT (IQ)  Definition : standardized measure of intelligence based on a scale in which 100 is average

INTELLIGENCE QUOTIENT (IQ)  What would an 8 year old child who scored at the mental age of 8’s IQ be?  No longer widely used  Schools have started to use the Otis- Lennon Ability Test to measure how successful a student will be in school

WECHSLER TESTS  WAIS III   WISC IV  See handout  WPPSI III

USES AND MEANINGS OF SCORES  Norms are established so that most people score near 100  95% of people score between  A little over 2% score over 130  Scorers below 70 have generally been classified as mentally handicapped  idiot, moron, and imbicile are dated terms  – mildly handicapped, but educable  – moderately handicapped, but trainable  – severely handicapped,  Below 25 – profoundly handicapped

WHAT DO THESE SCORES MEAN?  IQ scores are most useful when related to school achievement  Critics wonder if tests actually measure intelligence  Is success in school or the ability to take a test a real indication of such ability?

NATURE VS. NURTURE  Are scores affected by genetics or the environment?  Hereditability: the degree to which a characteristic is related to inherited genetic factors  Twins raised in similar environments are likely to have similar IQ’s  Head Start, poverty, quality of food  See NPR Article

CULTURAL BIAS  Definition : an aspect of an intelligence test in which the wording used in questions may be more familiar to peple of one social group than to another group  Example: “What would you do if you were sent ot buy a loaf of bread and the grocer said he did not have any more?”  Minority Students Answer: Go home  Correct Answer: Go to another store  When questioned, minority students reported that there was only one store in their neighborhood