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Strategies & Market Trends : 2026 TeoTwawKi ... 2032 Darkest Interregnum
GLD 399.01+0.1%Dec 19 4:00 PM EST
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To: Maurice Winn who wrote (4105)2/9/2006 1:30:59 AM
From: Crabbe  Read Replies (1) of 218612
 
I would tend to believe that mercury and lead and other heavy metals could be a possible explanation. The problem is that not all all tests show the same thing, there was indeed a trend up to 1963 of rising SAT and ACT test, both tests coordinate very closely with tests such as the Stanford Binet and Cattel. But beginning in 1963 and continuing into the late 1990's there was a constant decline in the overall test scores.

Perhaps the declining test scores from 1963 to the late 1990's can be attributed to tetra-ethyl lead in the gasoline supply of America. Certainly lead in the environment increased drastically until the 1980's, then with the removal of lead from gasoline perhaps the children born after this time had higher IQ's because of decreasing exposure to lead.

I would buy the Flynn Effect except for the fact that it presents the theory that through out the 20th century IQ scores rose at a constant rate of 3% a decade. Nutrition in the 30's and the rising not falling rate of lead in the environment from 1923 to the mid 1980's due to tetra-ethyl lead in gasoline.

The SAT and ACT scores tend to reverse lag the concentration of lead in the environment by about 15 years, which would match expectations for lowering of intelligence in an individual by lead exposure.

I don't totally reject the Flynn Effect, I just think the general statement is too simplistic.

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