Do IQ tests measure g?

by NancyLebovitz1 min read24th Nov 201010 comments

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IQ and g-factor
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I'm indulging in the simple pleasure of drawing large conclusions from a single study.... Why exams are nothing out of context:

the story about the maths ability of Brazilian street kids living in the in the favelas of Recife. This story helped both of us realise the importance of carrying out usability tests in context. Three researchers (see: Carraher, Carraher, and Schliemann 1985) carried out research with children aged 9 to 15. These kids had dropped out of school, and were selling sun screen, and chewing gum on the streets. The researchers worked out that they could set the kids questions by purchasing goods off them. For example, 1,000 minus 300 is the same as giving the kid a 1,000 Cruzeiros note for a product that costs 300 Cruzeiros. Multiplication can be done by asking the kids how much 3 of a product would cost. In these tests the Brazilian street kids scored 98%. But when they were put into a formalised test setting, and asked instead of how much would 3 apples cost or what 3×9 is, the kids performance dropped to just 37%.
What is scary is that the researchers later tested middle class children in a private school. These kids did very well in the formal exam. But when they had to do transactions with real money in the street, using the same maths, they failed in being able to do the transactions.

Is it possible that the correlation between g and success isn't about raw intelligence, it's about being able to access one's intelligence in situations (like classrooms) which involve thresholds for easily improving one's status?

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g is defined to be the thing that IQ tests, as a whole, measure. E.g. wikipedia:

Spearman named the common factor g for "general intelligence factor." In any collection of IQ tests, by definition the test that best measures g is the one that has the highest correlations with all the others

While the study you link to is pretty interesting, it doesn't claim anything about IQ, g, or intelligence.

Is it possible that the correlation between g and success isn't about raw intelligence, it's about being able to access one's intelligence in situations (like classrooms) which involve thresholds for easily improving one's status?

I'm not sure of what this means - what does it mean that "the correlation between g and success is about raw intelligence" ? Since g is pretty much an attempt to formalize what we mean by raw intelligence, that reads to me like "the correlation between raw intelligence and success is not about raw intelligence".

[-][anonymous]11y 3

Maybe an unfamiliar environment distracts them, or maybe a competitive environment makes them concentrate more, or maybe a familiar environment makes them comfortable, or maybe students don't wanna embarrass themselves by making stupid mistakes in class, or maybe the kids on the streets aren't able to multiply - they "memorise" the whole thing (3x2 =6; 3x3 = 9, etc.) to make the transactions faster.

I like this forum lol.

maybe the kids on the streets aren't able to multiply - they "memorise" the whole thing (3x2 =6; 3x3 = 9, etc.) to make the transactions faster.

Well, multiplication is done largely by memory for everyone for small numbers. There's a lot of evidence for this, such as fMRI studies showing memory related areas of the brain being active during multiplication that aren't active during addition. Also people with strokes who then lose the ability to multiply almost always have other memory impairments. If the kids on the street are using memorization then they are doing the same thing as everyone else.

Wow, this is quite an amazing point. Put people in an uncomfortable environment, and then they get distracted more easily (and they lose motivation), and their scores might drop. The effect of this varies from group to group, but it can be quite significant. Wow.

Well, it suggests that "good at arithmetic" should have a modifier for environment.

It would be interesting to find best environments for specific skills for individuals. Afaik, relatively little effort has gone into this.

Although I have to wonder if the real explanation was some sort of mixup, rather than a grand scale flaw in the testing methodology, I have met one person who I would estimate to have been at least as intelligent as myself, who revealed his tested IQ, and it was approximately half of my own. I don't remember if he ever mentioned what type of IQ test it was he took, but if the tests are at all properly designed, individuals of similar intelligence should not fall large distances apart from each other on opposite sides of the median depending on which test they took.

being able to access one's intelligence

One of the most insightful phrases ever on LW.

It is certainly true that IQ tests are better at measuring within group differences than between group differences. And I believe that IQ doesn't predict much success in the US once you control for education. But it does predict longevity when controlling for wealth and education. The IQ literature has a very serious lack of studies comparing the effects of IQ to wealth or education.