Your treatment of IQ is ridiculous. Give me access to a child for seven months, and I can increase their IQ score by 20 (and probably make myself an enemy in the process: IQ test drills are one of the dullest activities, since you can't even switch your brain off while doing them).
Intelligence is not a single axis thing. IQ test results are significantly influenced by socioeconomic factors. "Actual intelligence is hard to know" because it doesn't exist.
I have never yet known scientific racism to produce true results. I have known a lot of people to say the sorts of things you're saying: evidence-free claims that racism is fine so long as you're doing the Good Racism that Actually Works™, I Promise, This Time It's Not Prejudice Because It's Justified®.
No candidate genetic correlate of the g factor has ever replicated. That should be a massive flashing warning sign that – rather than having identified an elusive fact about reality that just so happens to not appear in any rigorous study – maybe you're falling afoul of the same in-group/out-group bias as nearly every group of humans since records begin.
Since I have no reason to believe your heuristic is accurate, we can stop there. However, to further underline that you're not thinking rationally: even if blue people were (on average) 2× as capable at spacial rotation-based office jobs than green people, it still wouldn't be a good idea to start with the skin colour prior and update from there, because that would lead to the creation of caste systems, which hinder social mobility. Even if scientific racism worked (which it hasn't to date!), the rational approach would still be to judge people on their own merits.
If you find it hard to assess the competence of your subordinates, to the point where you're resorting to population-level stereotypes to make hiring decisions, you're an incompetent manager and should find another job.
Does this make the child "more intelligent"? Not in any meaningful way! But they get better at IQ tests.
It's a fairly common protocol. I can hardly be said to have invented it: I was put through it. (Sure, I came up with a few tricks for solving IQ-type problems that weren't in the instruction books, but those tricks too can be taught.)
I really don't understand why people think IQ test results are meaningful. They're among the most obvious cases of Goodhart's law that I know. Make up a sport that most kids won't have practised before, measure performance, and probably that's about as correlated with the (fictitious) "g factor" as IQ tests are.
I'm not sure how you'd run a double-blind experiment on this. You can single-blind the experimenters, but the participants are always going to know whether they've been drilling IQ tests.
Your point about counterfactuals is good, but… subjectively, I ended up with a better understanding of IQ test genre conventions (which is also why I bang on so much about "culturally-specific": they really are). My speed at solving the problems doubled or tripled, and my accuracy went from 80%-ish to near 100%. This did not translate to any improvements to my real-life skill at anything (although, I suppose it might've generalised a bit to other multiple-choice exams). I've got a lot more evidence to analyse than just an n=1 scatter plot.
> the participants are always going to know whether they've been drilling IQ tests.
I'm not asking you to actually do this, but the participants (and experimenters!) don't necessarily have to know what you're testing. Maybe get one to drill IQ tests, one to drill Latin, one to drill chess and one to drill the piano.
Does your ability extend to IQ tests with other patterns? Also, does it extend to logic puzzles?
No, it actually slows me down on IQ tests that don't follow the genre conventions. (I used to approach them with a fresh mind – and I can still do that, if I have time to get into that mindset, but it's not always my default.) But I almost never see those, so…
It doesn't extend to logic puzzles, which I've always been quite bad at. (I find the Professor Layton games hard enough to be actively unfun, despite their beauty.) I can solve problems if they're contextualised, but my approach for solving logic puzzles is "identify a general algorithm, then execute it", which is quite slow.
As I've been telling you: IQ is extremely artificial; and doesn't measure general intelligence, because there's no such thing as "general intelligence". The "g factor" is a statistical regularity, but any statistician can tell you that while all sustained statistical regularities have explanations, they don't necessarily correspond to real things.
From time to time I see a press release to the effect that some movie star (Alyssa Milano was one) got an IQ score around the max of Raven's Progressive Matrices. I bet somewhere there is a psychologist who will coach you on it, across the street one will test you, and on the next block a PR agency that will make the press release.
I mean, there aren't that many questions on Raven, you could memorize them all, particularly if you've got the kind of intelligence that actors have -- being able to memorize your lines. (And that's something, I have a 1950-ish book about the television industry that makes a point that people expect performers to be a "quick study", you'd better know your lines really well and not have to be told twice that you are expected to do this or that. That's different from, say, being able to solve really complex math problems.)
Intelligence is not a single axis thing. IQ test results are significantly influenced by socioeconomic factors. "Actual intelligence is hard to know" because it doesn't exist.
I have never yet known scientific racism to produce true results. I have known a lot of people to say the sorts of things you're saying: evidence-free claims that racism is fine so long as you're doing the Good Racism that Actually Works™, I Promise, This Time It's Not Prejudice Because It's Justified®.
No candidate genetic correlate of the g factor has ever replicated. That should be a massive flashing warning sign that – rather than having identified an elusive fact about reality that just so happens to not appear in any rigorous study – maybe you're falling afoul of the same in-group/out-group bias as nearly every group of humans since records begin.
Since I have no reason to believe your heuristic is accurate, we can stop there. However, to further underline that you're not thinking rationally: even if blue people were (on average) 2× as capable at spacial rotation-based office jobs than green people, it still wouldn't be a good idea to start with the skin colour prior and update from there, because that would lead to the creation of caste systems, which hinder social mobility. Even if scientific racism worked (which it hasn't to date!), the rational approach would still be to judge people on their own merits.
If you find it hard to assess the competence of your subordinates, to the point where you're resorting to population-level stereotypes to make hiring decisions, you're an incompetent manager and should find another job.