Features #1-3 do not "rely heavily on intelligence". While intelligence certainly has a role, they rely much more heavily on training. All three also depend on knowing what is interesting, which is more a form of curiosity guided by knowing what other people know than a form of intelligence that can be measured by taking the SAT.
(I don't know enough about #4 or #5 to make a comment.)
People with graduate degrees have higher than average IQ, but people with higher IQ do not necessarily have graduate degrees.
That is, intelligence is a necessary (but not sufficient) condition to get a graduate degree in STEM. The other necessary conditions you mention (training, interest, etc.) are also important, but still require a baseline ability.
Even looking at undergraduate degrees, IQ is a significant factor in what degree is obtained. Physics and astronomy majors have an average of IQ [1] of over 130 -- that's 2 standard deviations above the mean. If interest, training, and hard work alone were sufficient to get a physics degree, we'd see a much lower average IQ among physics students.
I wrote "While intelligence certainly has a role, they rely much more heavily on training".
Everything you wrote just now agrees with my statement.
Originally you wrote "All five rely heavily on intelligence". It is that emphasis on "heavily" that I am disputing. I argue that it's less important than training, though of course not un-important.
I disagree with your interpretation of [1]. You wrote "Physics and astronomy majors have an average of IQ [1] of over 130". However, your [1] shows not a measure of IQ but an approximate estimate of IQ based on the cumulative SAT.
After showing the plots, your [1] then points out the correlation is only with the quantitative/analytical section of the SAT, and not the verbal, commenting "we see why this IQ estimation is potentially misleading."
> This tells us that the original plot is actually showing preference for quantitative majors: The higher the estimated IQ, the more quantitative/analytical the major, and the fewer women enrolling in those majors.
> This brings up an interesting question of how valuable the SAT is as a standardized test across all majors, if a higher SAT score is really only indicating that the student is better at solving quantitative/analytical problems. Not all majors require a high analytical aptitude, after all.
Your source therefore does not seem to be making the statement that "Physics and astronomy majors have an average of IQ of over 130" but that physics and astronomy require a high analytical aptitude, which is correlated to how well a student does on a test for analytical aptitude, which is correlated to the cumulative SAT score, which is correlated to g factor. That's a weaker conclusion than what you described.
In any case, undergraduate study does not require the ability to identify what is scientifically interesting, which is a key point of my objection to your original statement.
EDIT: Also, your [1] points out "men and women have about the same IQ" then shows that physics and astronomy has a greatly disproportionate number of men than women. Thus, being male is a stronger correlation for those undergraduate degrees than intelligence. Thus suggests that some other factor than general intelligence is biasing the numbers.
Again, you are only exposing group bias. Doctorates are largely predicated on test scores - they are a filter on who can access a defense committee - of course those with doctorates will have higher prior test scores; those with high test score were intentionally picked as doctoral candidates, in part, because of their test score(s).
What I think you're trying to say is that intelligence is irrelevant to getting a Doctorate because test scores, not intelligence, are the factor. But of course doctorates are based on test scores. That's because test scores are an indicator of intelligence, and so admissions committees filter based on test scores in order to filter on intelligence. So that means yes, admissions depends on test scores, but no, test scores are not independent of intelligence.
That is:
P(high IQ | high test score) > P(low IQ | high test score)
What you're trying to say is that getting a doctorate a degree doesn't depend on intelligence, and is just an indicator of some "group bias". What I'm saying is that test scores are correlated with IQ. This implies that if you do not have high intelligence, it is going to be extremely difficult to get the test scores required to get into graduate school, and thus intelligence is required for admission.
In other words, intelligence is indeed a necessary but not sufficient condition to get a graduate degree in STEM.
No one thinks intelligence is irrelevant to getting a PhD.
The question is, how do you know that getting a PhD relies "heavily on intelligence"? How do you know that intelligence has a strong or weak correlation? Or that there isn't some sort of threshold, where an effective IQ of at least 90 is important, but 140 is no more important?
What other factors have you considered, and why have you concluded they are less significant to getting a PhD than the intelligence that can be measured by the SAT?
jsprogrammer has, I think, a different point. Let's suppose that everyone has an equal chance of getting a PhD should they be admitted into graduate school. Let's also suppose that the selection committees believe that test scores are correlated with intelligence, and that only those with a high test score (and presumably higher intelligence) should get into graduate school.
This would end up with PhDs who all had good test scores, simply because of the selection bias. It would not reveal anything about the underlying population, because it confounds any association between intelligence and getting a PhD.
The people who get a PhD this way become members of a selection committee. They know the process worked for them, and repeat it, making this a stable system.
How do you know that PhD students now aren't selected in part because of a cultural belief which places a higher weight on test scores than is justified? How much of an effect does that bias have on the correlations you keep pointing to?
OK, let's use your hypothetical that if we accept everyone, that they will have equal graduate attainment (regardless of test scores).
Then, we would expect that there would be little correlation between testing scores and outcomes. Especially whether they get a degree. For instance, someone who gets a lower test score will have the same outcomes as someone who gets a higher test score.
But that's not what the research suggests:
> The report, which examined 1,753 studies, found that GRE scores could help predict students' graduate grade point averages, first-year GPAs, ratings from faculty, exam scores, degree attainment and number of citations earned. The specific subject tests were even stronger indicators of students' performance.
I specifically said that intelligence was a factor.
The hypothetical was meant to show that your analysis was insufficiently sensitive, not to posit that the hypothetical was actually the case.
You have an odd habit of pointing to secondary and preprint material, rather than the primary literature. Your APA links to several papers, including http://www.drtomascp.com/uploads/HungryMind_PPS_2011.pdf , titled "The Hungry Mind: Intellectual Curiosity Is the Third Pillar of Academic Performance". It concludes:
> The current study suggests that traditional sets of predictors of academic performance, notably general intelligence and Conscientiousness, should be accompanied by a third factor: intellectual curiosity. Jensen (1998) stated that “[general intelligence] g acts only as a threshold variable that specifies the essential minimum ability required for different kinds of achievement. Other, non-g special abilities and talents, along with certain personality factors ..., are also critical determinants of educational and vocational success” (p. 544–545). A remarkable number of studies on determinants of academic
achievement have focused exclusively on ability and effort; the present findings, however, recommend further expanding the “g-nexus” for a better understanding of individual differences in academic performance. The latter requires—beyond intelligence and effort—a hungry mind.
It does say "intelligence is the single most powerful predictor of academic performance", then said:
> intelligence sustained the strongest effect on academic performance with a path weight
of .35. TIE and Conscientiousness had slightly lower, identical path parameters of .20.
I believe that means that the other two legs together are more important than intelligence alone.
The specific report isn't linked to in the article you posted, but I wonder how closely the first year grad curiculi resembled GRE tests and why the tests were apparently not predictive beyond a single academic year.
(I don't know enough about #4 or #5 to make a comment.)