The Flynn Effect
Flynn posited three conclusions
1. These effects aren't real but a result of sampling error 2. General population is becoming more sophisticated at taking IQ tests 3. IQ increases reflect a real change in the intelligence of the general population
How did it begin and when?
1981, Flynn investing data from the Armed forces and found that African Americans had been gaining on the scores of the Whites in this sample. --he wondered if these gains could be real and if the Armed forces tests was a "genuine" measure of intelligence like the Weschler test The same participants were given new and old tests, participants did far better on the older one. WISC scores changes from 100 to 108
Other Explanations by Flynn
As far as he is concerned, IQ tests gains are not real, and reflect the fact that IQ tests don't measure intelligence.
Flynn's Conclusions
Flynn argues that we can't really be getting any smarter -Were all generations mentally retarded before us? Example of Dutch teacher -The Ravens Progressive Matrices Test doesn't measure intelligence but rather a correlate with a weak causal link to intelligence; the same may apply to all IQ tests -Flynn says Netherlands alone has over 300,000 potential geniuses, cultural renaissance.
Flynn's next study
(1984) Found 73 studies make 18 different combination comparisons. -Remarkably consistent findings in all but one, and he noted that he had observed a real effect Observations were complicated by declining SAT scores in 1941-1981
Next test by Flynn
(1987) Data from 14 countries, the data from Netherlands, Belgium, and Norway most closely followed Jensen's criteria. -Father/son comparison in Dutch data. Sons were 18 points higher than fathers separated by 27.5 years. Flynn demonstrated that even genetically related people had the flynn effect in between them -Data from 14 nations demonstrated IQ gains from 5-25 with average of 15 points --Largest gains found on culture-free tests --Demonstrated Flynn effect in every country he had tested.
Greenfield
(1998) Argues for influences of technologically driven changes in visual environment that may affect models of thought required by mental tests
Schooner
(1998) Influence of environmental complexity and modernization made the change
Williams
(1999) Array of environmental influences including educational attainment of parents, decreased family size, and increased family resources
Dickens and Flynn
(2001) They propose a solution where small changes in the environment are multiplied by genes to produce the kind of IQ gains that Flynn saw Small changes in environment lead to lasting impact. 4 possible multipliers 1. Industrialization 2. Increased leisure time 3. Fewer children in families 4. Increased cultural value of on-the-spot abstract problem solving (Flynn, 2006)
More Flynn conclusions
-Learned content has inhibited rather than promoted IQ gains. IQ gains since 1950 reflect increase on problem solving ability, not just learned content -Between group differences on intelligence tests may not be equivalent to real intelligence tests
4 Critera to test IQ Raised by Jensen
1. Sample bias has to be eliminated so don't test mass groups 2. Emphasis placed on mature subjects 3. Tests should remain unaltered throughout generations 4. Emphasis placed on culturally reduced tests
Neisser (1998)
Racial Differences -Said the 3 point per decade increase meants the test performance of Black Americans today is roughly equivalent to that of Whites in 1940. Now clear a gap of this size can be easily attributed to environmental differences
Disagreements to Flynn
Schooner (1998) Greenfield (1998) Williams (1999)
Influence of Nutrition
Sigman (1998), Martoell (1998), and Lynn (1998)