Actually academic achievement is something IQ tests excel at predicting quite well. We also, on average, see clear differences in average intelligence between people with differences in academic achievement, if one was tempted to dismiss the greatest achievement of psychometrics out of hand based on this.
I don’t deny that. I’m not one of those IQ-doesn’t-measure-anything people.
conscientiousness isn’t another thing the educational system selects for, it is the second best predictor, but it is just that, second best.
Okay, so: When you measure a correlation, you aren’t just measuring how two things are related. Construct validity plays a huge role.
If you just asked people “How smart are you” and correlated it with grades, you’d likely see a positive correlation. But if you give them Raven’s Progressive Matrices, you’d see a much stronger correlation with grades.
The correlation reflects not just the relationships between underlying phenomenon, but the degree to which you have successfully measured the underlying phenomenon. Unless you’re measuring opinions or something, self-reports suffer from all sorts of issues with validity that cognitive tests do not.
So when you compare simple self-reported conscientiousness to IQ (which is, as you said, the greatest achievement in psycho-metrics), you’re pitting a mouse against a lion.
The study I cited further down the thread, which says that willpower is more important than IQ, was able to get that result because they put a lot more effort into measuring willpower than other studies. The willpower variable was a composite of several self reports, teacher reports, parent reports, and a behavioral delay of gratification task. This composite willpower score will have more validity than any of its individual components.
(It’s the same with IQ: a composite IQ test, with verbal tests, visuospatial tests, reaction time, etc will be more g-loaded (against a separate test battery,) than any individual measurement, and will probably predict grades better too. Excuse my glossing over things—see here for an example of how CCFT’s low question diversity results in lower g)
Don’t be too quick to downplay the importance of conscientiousness—a lot of the weaker correlations can be chalked up to the difficulty of measuring the underlying thing.
If you just asked people “How smart are you” and correlated it with grades, you’d likely see a positive correlation. But if you give them Raven’s Progressive Matrices, you’d see a much stronger correlation with grades.
That’s not self-evident to me, if only because people’s self-perception of smartness is likely to be (partially) driven precisely by their grades.
I agree that its very plausible that grades affect self perception. However, I have low confidence that it would be more predictive than IQ.
Same could be said for conscientiousness, but thus far it seems like the behavioral testing and the reports from grade-naive “homeroom” teachers seem to increase the correlation rather than decrease it compared to self-report alone.
I don’t have strong opinions on the subject, but I wouldn’t necessarily expect uniform results across the IQ spectrum. It might well be that different things are more predictive at different ends of the IQ curve.
In particular with respect to IQ and conscientiousness, it seems to me that at high IQ levels the “necessary-for-A+” IQ tops out and conscientiousness starts to dominate, while it’s the reverse with low IQ—if you’re just not smart enough, conscientiousness won’t help much.
it seems to me that at high IQ levels the “necessary-for-A+” IQ tops out and conscientiousness starts to dominate, while it’s the reverse with low IQ—if you’re just not smart enough, conscientiousness won’t help much.
I low-confidence-agree with you. That seems gut-level correct, and fig 1 supports this notion but I don’t know the extent that trend should be trusted and there are other possibilities.
If I had to guess I’d rephrase it as ” both have diminishing returns, but the diminishing returns on IQ are both more dramatic than those on conscientiousness.”
actually, looking at figure 1 it doesn’t look like self discipline has diminishing returns at all, whereas it looks like IQ does. Just eyeballing, the “IQ test ceiling” for GPA is the 3rd quintile of this population’s OLSAT7 lv G scorers whereas Self Discipline doesn’t even hit a ceiling. But conclusions via eyeballing would be criminally non-rigorous :)
I don’t deny that. I’m not one of those IQ-doesn’t-measure-anything people.
Okay, so: When you measure a correlation, you aren’t just measuring how two things are related. Construct validity plays a huge role.
If you just asked people “How smart are you” and correlated it with grades, you’d likely see a positive correlation. But if you give them Raven’s Progressive Matrices, you’d see a much stronger correlation with grades.
The correlation reflects not just the relationships between underlying phenomenon, but the degree to which you have successfully measured the underlying phenomenon. Unless you’re measuring opinions or something, self-reports suffer from all sorts of issues with validity that cognitive tests do not.
So when you compare simple self-reported conscientiousness to IQ (which is, as you said, the greatest achievement in psycho-metrics), you’re pitting a mouse against a lion.
The study I cited further down the thread, which says that willpower is more important than IQ, was able to get that result because they put a lot more effort into measuring willpower than other studies. The willpower variable was a composite of several self reports, teacher reports, parent reports, and a behavioral delay of gratification task. This composite willpower score will have more validity than any of its individual components.
(It’s the same with IQ: a composite IQ test, with verbal tests, visuospatial tests, reaction time, etc will be more g-loaded (against a separate test battery,) than any individual measurement, and will probably predict grades better too. Excuse my glossing over things—see here for an example of how CCFT’s low question diversity results in lower g)
Don’t be too quick to downplay the importance of conscientiousness—a lot of the weaker correlations can be chalked up to the difficulty of measuring the underlying thing.
That’s not self-evident to me, if only because people’s self-perception of smartness is likely to be (partially) driven precisely by their grades.
I agree that its very plausible that grades affect self perception. However, I have low confidence that it would be more predictive than IQ.
Same could be said for conscientiousness, but thus far it seems like the behavioral testing and the reports from grade-naive “homeroom” teachers seem to increase the correlation rather than decrease it compared to self-report alone.
I don’t have strong opinions on the subject, but I wouldn’t necessarily expect uniform results across the IQ spectrum. It might well be that different things are more predictive at different ends of the IQ curve.
In particular with respect to IQ and conscientiousness, it seems to me that at high IQ levels the “necessary-for-A+” IQ tops out and conscientiousness starts to dominate, while it’s the reverse with low IQ—if you’re just not smart enough, conscientiousness won’t help much.
I low-confidence-agree with you. That seems gut-level correct, and fig 1 supports this notion but I don’t know the extent that trend should be trusted and there are other possibilities.
If I had to guess I’d rephrase it as ” both have diminishing returns, but the diminishing returns on IQ are both more dramatic than those on conscientiousness.”
actually, looking at figure 1 it doesn’t look like self discipline has diminishing returns at all, whereas it looks like IQ does. Just eyeballing, the “IQ test ceiling” for GPA is the 3rd quintile of this population’s OLSAT7 lv G scorers whereas Self Discipline doesn’t even hit a ceiling. But conclusions via eyeballing would be criminally non-rigorous :)