Rationally Speaking | Official Podcast of New York City Skeptics - Current Episodes - RS144 - Bryan Caplan on "Does parenting matter?"
"If you go and take a look at the 1960s, which is the tail end of the baby boom, actually moms on average spent less time taking care of their kids than they do today, even though they had far more kids, even though they were less likely to have jobs outside the home and even though dads helped a lot less. Still back in those days moms were doing less...
Out of the people who do adopt, there is a lot of reason to think that in fact, there is evidence that if the adopted children is having trouble, the adopting parents put in extra for them or they compensate for whatever problems the adopted child might have. I'd say that there's very good evidence that adopted kids are treated very similarly to biological children. There's been stuff done on these things like, do adopted kids get a normal share in inheritance, and they do...
[The effects of parenting are] generally short run effects. To use a term that comes up a lot in this research, there’s “fade out” -- so while you can change your kid in the short run, over the long run they tend to go back to where they would've been if they've been raised by a very different family...
Here's the important thing to realize about all of these estimates of the effect of nature, the effect of nurture -- is that they include all effects, direct or indirect, as long as they actually are caused by being raised by one family or having certain genes. So for example if you go and find there is a genetic effect on income, this could mean that there's actually a gene for money making, but it could also mean that there's a gene for good looks and that good looks are rewarded in the market...
There's one very interesting study of church attendance that finds that by the time that you were in your mid-thirties there's no longer any effect of the family that raised you on how much you go to church...
There are a number of different measures of health that researchers looked at using these adoption or twin methods. The most objective one, of course, is how long you live, your lifespan. In that one a lot of our best evidence comes from Scandinavia because they've been keeping records on everybody for over a century. And the punch line there is it's very hard to see an effect of upbringing on how long you live...
How much your parents affect your obesity -- and that's one of the very strongest results, looks like parents do not change your adult weight. Being raised by a family of health nuts is not going to make you thinner. If your biological relatives are overweight, then you are likely to be overweight, and the fact that you are raised by a family that valued keeping very thin, that's not going to change your weight...
Why is it that the long run effect will be smaller than the short run effect? You might think the short run effects will all tend to add up into one big long run effect, but the main thing to remember is that as people get older, they gain more and more control over their own lives, and if something just doesn't feel right for them, something you've been sort of pushing on them that just doesn't resonate with them, then the older they get, the greater their opportunity is to do what they want rather than what you raised them to do...
One of the few things that actually you can get very good permanent results on, is if kids have sleeping problems. Because there is the Ferber method where you just let kids cry it out for a little while and then you don't immediately comfort them. So as you might guess, if kids immediately get attention whenever they cry, they cry a lot and they're bad sleepers. Experiments were done where some kids, you just do whatever you want, some kids get the Ferber method where they at least let them cry for five minutes before you go to them, other kids just let them cry it out, it doesn't matter how long it takes. This works, but not only does it work, once you get a kid on the right track of sleeping they generally don't stop sleeping again. And once they start sleeping then they aren't awake to go and want to get attention anymore. So that's one where as long as you do it for a good six months, even kids with pretty bad sleep problems can be fixed with this problem, fixed from parents’ point of view anyway...
Identical twins who were raised in different homes were more similar in their adult happiness than identical twins that were raised in the same home... there is a story that people told – it’s just a story but, my first two sons are identical twins, so it does resonate with me a bit. This story just says, that when they were raised together they naturally tried to differentiate themselves in an artificial way just to get their own niche: I'm the hard working twin, I'm the lazy twin. I'm the cool twin, stuff like that...
Tax records for this giant sample of twins. So you know exactly how much legal income they're reporting for many decades, and what he found on income was that when you're in your 20s, there we still do see this effect of upbringing on your income, but by the time you're in your 30s it goes away...
The resemblance between parent and child for divorce is highly genetic, maybe entirely genetic. You can actually see that the similarity of identical twins for whether or not they're divorced is much higher than fraternal twins, which is a smoking gun of a large genetic effect. And really if you go and read a bit about the effect of personality in general on divorce, it's nothing too surprising. People who are disagreeable and have low conscientiousness and who have bad attitudes, have high chances of getting divorced...
I am as your readers probably don't know, a long time libertarian, but I will say almost every book of libertarian political philosophy embarrasses me"