Oops. Accidentally dropped a paragraph about whether you could increase height/SAT scores across the board with the existing policy levers. In that case, a high heritability doesn’t directly say that that’s unlikely, but you would at least have to expect to increase your policy setting to the point where most people are getting more of the nutrition or education or whatever than is currently a few standard deviations above average, since otherwise if less than that much of your policy was having an effect, you would expect to already see it in the heritability measurement. So heritability doesn’t say that feeding kids 10,000 calories a day or sending them to school for 12 hours a day won’t have effects on height/SAT scores, but as a general rule you’d be looking at such extreme interventions that it’s probably not a good direction to go.
I’m still so confused(through no fault of your own, I think you’re right, it just doesn’t fit in my head). Let me try to walk through my thought process.
I assume heritability of SAT score is probably different if you sample across USA, or just upper-mid class suburbs or just South Side Chicago, or just rural Eastern Europe, or just Malawi during a famine. Right? Given that environments are pretty radically different.
What heritability score are we using to determine if policy interventions matter or not? Is the first step to make sure that the region we want to improve has an environment that mimics ‘successful’ regions? Heritability would be very high in a homogenous environment(since that’s the only variation), but it goes down as more varied environments are added to the sample. Heritability is very high if we just look at rich area USA schools, lower if you sample all USA and even lower if we sample the whole world?
Also how is this linked to amplitude of effect? Super high heritability of SAT/IQ in say homogenous Denmark, but presumably the actual variation in scores is lower than in a global sample. Is there a way to say genetics account for +/- 5 points of IQ? So if you’re measuring IQs of 95-105 in your area that’s probably all genetic effects and policy interventions can’t do much?
Edit. I realize now that this is mostly Insub’s point below, but less coherent.
Pretty much. If an intervention is well outside of the set of experiences of your population, there’s probably a reason for that. Perhaps it’s just too new, but it’s likely that it’s inconsistent with the way the culture usually functions (its values as actually implemented) and/or has fairly obvious side effects.
Oops. Accidentally dropped a paragraph about whether you could increase height/SAT scores across the board with the existing policy levers. In that case, a high heritability doesn’t directly say that that’s unlikely, but you would at least have to expect to increase your policy setting to the point where most people are getting more of the nutrition or education or whatever than is currently a few standard deviations above average, since otherwise if less than that much of your policy was having an effect, you would expect to already see it in the heritability measurement. So heritability doesn’t say that feeding kids 10,000 calories a day or sending them to school for 12 hours a day won’t have effects on height/SAT scores, but as a general rule you’d be looking at such extreme interventions that it’s probably not a good direction to go.
I’m still so confused(through no fault of your own, I think you’re right, it just doesn’t fit in my head). Let me try to walk through my thought process.
I assume heritability of SAT score is probably different if you sample across USA, or just upper-mid class suburbs or just South Side Chicago, or just rural Eastern Europe, or just Malawi during a famine. Right? Given that environments are pretty radically different.
What heritability score are we using to determine if policy interventions matter or not? Is the first step to make sure that the region we want to improve has an environment that mimics ‘successful’ regions? Heritability would be very high in a homogenous environment(since that’s the only variation), but it goes down as more varied environments are added to the sample. Heritability is very high if we just look at rich area USA schools, lower if you sample all USA and even lower if we sample the whole world?
Also how is this linked to amplitude of effect? Super high heritability of SAT/IQ in say homogenous Denmark, but presumably the actual variation in scores is lower than in a global sample. Is there a way to say genetics account for +/- 5 points of IQ? So if you’re measuring IQs of 95-105 in your area that’s probably all genetic effects and policy interventions can’t do much?
Edit. I realize now that this is mostly Insub’s point below, but less coherent.
Pretty much. If an intervention is well outside of the set of experiences of your population, there’s probably a reason for that. Perhaps it’s just too new, but it’s likely that it’s inconsistent with the way the culture usually functions (its values as actually implemented) and/or has fairly obvious side effects.