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Geoff332 · Sep 2, 2003, 08:10 pm

I notice you not answering my questions. Where is your evidence of IQ, racism and the relationship between the two.

Circularity of logic?

IQ is a concept. It was developed by Spearman (among others) who hypothesised that there was a single factor that underlay all intelligence -- or more specifically the quality of performance on cognitive tasks. He assumed this to be true (if you don't believe me, go and have a read of his "The nature of 'intelligence' and the principles of cognition"). Because of this assumption, he developed a methodology -- factor analysis -- to identify that factor. The mathematics are pretty tricky (and not something I really specialise in), but the basic principle is factor analysis is always going to return a 'strongest' factor which is considered to be G.

The problem is, this tends to account for a relatively limited amount of the variance in performance on cognitive tasks -- around 20-30%. Other factors explained nearly as much -- suggesting that there might be mutliple independant dimensions to intelligence. However these would have challenged the thesis of G (and, consequently the notion of IQ). So they were basically ignored (the process was a lot more complex; Spearman was a very competent gentleman). But the basic principle is that G is, at best, a questionable concept that has a degree of empirical support but no conclusive proof of validity. Sociologically, one would call the process objectification. Philosophically, one would call it tautological (which, rather than circularity is a better description of my reasoning). The process started with an abstract idea (G), developed a methodology driven by this idea (factor analysis) and applied it to a dataset (intelligence tests) to support the original thesis. The process has become highly self-referential (we know intelligence exists because we can measure intelligence. We can measure intelligence because we know intelligence exists.)

I suspect you will not answer my questions, nor accept this analysis. If you decide to do neither, can you please explain your decision.

Sep 2, 2003, 08:10 pm	#29 (permalink) (top)
Geoff332 Igneous Magma Location: New Zealand Posts: 309	I notice you not answering my questions. Where is your evidence of IQ, racism and the relationship between the two. Circularity of logic? IQ is a concept. It was developed by Spearman (among others) who hypothesised that there was a single factor that underlay all intelligence -- or more specifically the quality of performance on cognitive tasks. He assumed this to be true (if you don't believe me, go and have a read of his "The nature of 'intelligence' and the principles of cognition"). Because of this assumption, he developed a methodology -- factor analysis -- to identify that factor. The mathematics are pretty tricky (and not something I really specialise in), but the basic principle is factor analysis is always going to return a 'strongest' factor which is considered to be G. The problem is, this tends to account for a relatively limited amount of the variance in performance on cognitive tasks -- around 20-30%. Other factors explained nearly as much -- suggesting that there might be mutliple independant dimensions to intelligence. However these would have challenged the thesis of G (and, consequently the notion of IQ). So they were basically ignored (the process was a lot more complex; Spearman was a very competent gentleman). But the basic principle is that G is, at best, a questionable concept that has a degree of empirical support but no conclusive proof of validity. Sociologically, one would call the process objectification. Philosophically, one would call it tautological (which, rather than circularity is a better description of my reasoning). The process started with an abstract idea (G), developed a methodology driven by this idea (factor analysis) and applied it to a dataset (intelligence tests) to support the original thesis. The process has become highly self-referential (we know intelligence exists because we can measure intelligence. We can measure intelligence because we know intelligence exists.) I suspect you will not answer my questions, nor accept this analysis. If you decide to do neither, can you please explain your decision.