Bryan Caplan has a newish book called Selfish Reasons to Have More Kids. The core argument is that people overestimate what they can do as parents, and so they enjoy parenting much less (and their children enjoy childhood much less) than they otherwise would.
The evidence for this is that twin studies reveal very small or nonexistent parenting effects for important life outcomes. People have a hard time accepting this. A lot of the activities parents force on their kids are actually about status maneuvering within the parents’ peer group.
On amazon the book has an interesting one star rating that asserts the bulk of the evidence marshaled in support of the core argument are twin studies.
My distant impression is that many twin studies are methodologically questionable (being suspect to begin with because of congruence with the fundamental attribution error and in being problematic because they rarely look for good confounds) and so this review reduced my trust in summaries of the book and my interest in reading it for details.
As someone who has read the book, could you comment on the review?
Actually, I think that review is pretty awful. For one thing she seems to confuse Caplan’s actual claim, that parenting choices tend to have small to nonexistent effects on life outcomes, with a much stronger claim that environmental effects are tiny. From the review:
Yet even the studies he quotes acknowledge that Nurture has quite an effect. For instance, the MN twin study, quoted often, assigns heredity a 64-74% accountability for IQ differences among twins. That leaves as much as 36% of it changeable due to parental choices and upbringing.
This implies that all non-heritable variance could be due to parenting effects, when in fact unshared environment is known be accountable for most of the remaining variance. That eliminates the review’s main argument against the book.
I feel that this book was simply produced to make money. After the huge success the “Battle Hymn of the Tiger Mother”, it makes sense to write a book, basically opposed to the points in the best seller. It’s a “jump on the band wagon” move.
This is an obvious failure, since Caplan has been planning/researching/writing this book for years, long before Chua’s book came out.
So moms like me, who were worried that all your efforts are a waste, fear not, we have a good 50% control or more to mold our children into happy, healthy, successful people. Keep up the hard work!
And here we see the reason for possible motivated cognition by shopper8424. She doesn’t want to believe that her efforts have been in vain.
Twin studies are considered sound by psychometricians, and most of the criticism I’ve seen has been from ideologically opposed people who are not psychometricians.
Hmm… I guess I sort of asked for that, so maybe I shouldn’t complain… :-P
However, to be more precise, my question was not whether the reviewer was perfectly correct in all respects (where I can see for myself that she’s not), but whether the substance of her criticisms was sound based on having read Caplan (which I can’t do unless I read Caplan, as you have).
For example, another reviewer over on Amazon also explained that her attribution of “band wagon jumping” was wrong, but neither their correction or yours helps me judge Caplan at a distance. And you dismiss her due to motivated cognition but it sounds like Caplan is also a parent and so he could be engaged in motivated cognition to defend his laziness. So rather than assume either side is being dumb because someone can invent a just-so story to predict that they would say what they said if they were engaging in motivated cognition, I’d rather just let people talk and then filter the content for evidence and reasoning that’s worth retaining within a personal stock of models and lemmas. I’ve read shpper8424 but I haven’t read Caplan’s book, and so I was hoping that you could do this cognitive work for me :-)
However, it appears to me that you and I have different contextual understandings of shopper8424′ point, so maybe I can spell out the substantive point in her text that I was interested in hearing about. I understood her to simply be pointing out a broad flaw within Caplan’s book: that his advice was massively more specific than was warranted by the evidence he marshaled to support the advice.
For example, she spells out some of Caplan’s particular claims:
He specifically says to use TV and video games as a babysitter (pg. 25) and to stop “policing” (as he labels it) the kids’ shows, movies, games, etc… (pg.29) and to get fast-food for dinner.
She also spells out the justification he uses to support this evidence:
He says that this is all OK since “research provides strong evidence that parents barely affect their children’s prospects” (pg 4)… The studies that he quotes state that somewhere between 46-70% of how your child turns out is based on heredity.
Then she points out that this isn’t very strong evidence, with low sample sizes and no actual power to dismiss any particular set of practices that could account for some of the outcome.
That still leaves room for a parent to give their child a better life. Most nature vs. nurture studies settle that around 47-58% is due to heredity. He found some studies that actually set that variance to 70% for some variables, very high compared to most studies, and based on not much more that 100 sets of twins! How valid can that be? Remember, the Nurses’ Health Study is based on 238,000 people, now that is a good pool of people to base studies on.
She also offers (admittedly without citation and mixed with stuff that appears suspicious to me) alternative studies that could fill in some of the causal gap between human genetic variations and “everything we observe about human outcomes”:
For instance, less TV often leads to better grades in school, studies have shown, yet the book promotes using the TV as a babysitter and not even “policing” what your toddler is watching....another example? The book promotes relaxing by just getting fast food...and tons of studies are done on how foods like that create numerous health problems and healthy, organic if possible, homemade meals will increase your chances of having a healthier child and adult.
An argument against shopper8424 that doesn’t help me at all would be that “She doesn’t want to believe that her efforts have been in vain” and “most of the criticism I’ve seen has been from ideologically opposed people”.
A good argument against her, that would be quite helpful would be that Caplan’s book only mentions the twin studies as being consistent with his general advice, and also provides specific studies that how neither diet nor media habits substantively affecting human efficacy outcomes. Maybe he could also report that it doesn’t help to teach your children to meditate or program computers or read books for pleasure. Maybe he could claim that it doesn’t matter if they have violin lessons versus sitting in their bedroom listening to popular music that glorifies violence and the degradation of women. Maybe they shouldn’t be encouraged to play sports and you shouldn’t waste time ferrying them to soccer games when they’re 11. Maybe it doesn’t matter if you homeschool, versus sending kids to a school with metal detectors and class sizes of 70, versus sending them to a private Montessori school where they’ll start being able to start building a social network that enables them to navigate the subcultures of the rich and powerful when they are in their 40′s.
To restate my question: Does Caplan talk about details, or just twin studies? Does he give specific advice about “safe ways to slack” and show that this advice doesn’t harm long term outcomes? Does he cherry pick studies to find those that report the most extreme and shocking results (using a study that found heritability of 0.7 instead of 0.35 and not explaining that there was a range of values)?
To restate my question: What content in Caplan’s book can be mustered in response to a counter argument claiming that that heritability studies are weak for giving precise behavioral advice when clear thinking (and maybe even other studies) about the specific details of the advice show that some details matter?
However, to be more precise, my question was not whether the reviewer was perfectly correct in all respects (where I can see for myself that she’s not), but whether the substance of her criticisms was sound based on having read Caplan (which I can’t do unless I read Caplan, as you have).
You seem to have wilfully ignored the main point I made, which is this:
This implies that all non-heritable variance could be due to parenting effects, when in fact unshared environment is known be accountable for most of the remaining variance. That eliminates the review’s main argument against the book.
See, she is arguing against the twin/adoption studies based on the idea that the remaining environmental influence could be parenting, when Caplan explicitly points out that this isn’t the case. Unshared environment explains remaining variance. That was her sole substantive point (the rest being obviously false ad-homs and claims about some unspecified “other studies”).
To restate my question: What content in Caplan’s book can be mustered in response to a counter argument claiming that that heritability studies are weak for giving precise behavioral advice when clear thinking (and maybe even other studies) about the specific details of the advice show that some details matter?
Other studies cannot show that a parenting style detail matters without controlling for heritability. People frequently see studies that say (for example) kids who eat junk food are fat as adults, and assume this is due to childhood environment (controlled by parents). In fact, twin studies have shown that heritability for bmi is ~.80, with the remaining variance due mostly to unshared environment.
Now, if you want to dismiss the vast literature twin/adoption studies out of hand due to “confounds” (you haven’t specified), then, go ahead I guess. But you should have very strong reasons, since twin and adoption studies are considered the gold standard by the relevant social scientists.
Does Caplan talk about details, or just twin studies?
Yes. It’s a fairly long books, so he discusses may specific examples.
I should also address this, I guess:
Maybe he could also report that it doesn’t help to teach your children to meditate or program computers or read books for pleasure. Maybe he could claim that it doesn’t matter if they have violin lessons versus sitting in their bedroom listening to popular music that glorifies violence and the degradation of women. Maybe they shouldn’t be encouraged to play sports and you shouldn’t waste time ferrying them to soccer games when they’re 11. Maybe it doesn’t matter if you homeschool, versus sending kids to a school with metal detectors and class sizes of 70, versus sending them to a private Montessori school where they’ll start being able to start building a social network that enables them to navigate the subcultures of the rich and powerful when they are in their 40′s.
I think Caplan would say, you should do those things if you would consider it worth your time even if it doesn’t contribute to adult success for your kids (it probably won’t). If you enjoy classical music, there is a good chance you kid will as well. He’s mostly against dragging your kid to “enriching” things or stressing out because your kid likes rap.
He’s mostly against dragging your kid to “enriching” things or stressing out because your kid likes rap.
I appreciated this line. It communicated something substantive about Caplan’s opinions and the amount of evidence for them that I can expect to find in his book. Thank you.
In the meantime, I don’t think twin studies should be entirely dismissed, I just don’t think they explain as much, or can be safely used in the ways they are typically deployed in second order analysis. If you are interested in understanding my concerns here, the Shalizi link from my first attempt to communicate with you (the one that’s been voted down to −1 for reasons I don’t understand) is a good source. I didn’t repeat the points because I thought you (and anyone else who was interested) would be able to follow that link and understand the relevance without clogging up the thread with extraneous details.
Bryan Caplan has a newish book called Selfish Reasons to Have More Kids. The core argument is that people overestimate what they can do as parents, and so they enjoy parenting much less (and their children enjoy childhood much less) than they otherwise would.
The evidence for this is that twin studies reveal very small or nonexistent parenting effects for important life outcomes. People have a hard time accepting this. A lot of the activities parents force on their kids are actually about status maneuvering within the parents’ peer group.
Very much this. In fact, I intend to sponsor a review of this book for LW.
On amazon the book has an interesting one star rating that asserts the bulk of the evidence marshaled in support of the core argument are twin studies.
My distant impression is that many twin studies are methodologically questionable (being suspect to begin with because of congruence with the fundamental attribution error and in being problematic because they rarely look for good confounds) and so this review reduced my trust in summaries of the book and my interest in reading it for details.
As someone who has read the book, could you comment on the review?
Actually, I think that review is pretty awful. For one thing she seems to confuse Caplan’s actual claim, that parenting choices tend to have small to nonexistent effects on life outcomes, with a much stronger claim that environmental effects are tiny. From the review:
This implies that all non-heritable variance could be due to parenting effects, when in fact unshared environment is known be accountable for most of the remaining variance. That eliminates the review’s main argument against the book.
This is an obvious failure, since Caplan has been planning/researching/writing this book for years, long before Chua’s book came out.
And here we see the reason for possible motivated cognition by shopper8424. She doesn’t want to believe that her efforts have been in vain.
Twin studies are considered sound by psychometricians, and most of the criticism I’ve seen has been from ideologically opposed people who are not psychometricians.
Hmm… I guess I sort of asked for that, so maybe I shouldn’t complain… :-P
However, to be more precise, my question was not whether the reviewer was perfectly correct in all respects (where I can see for myself that she’s not), but whether the substance of her criticisms was sound based on having read Caplan (which I can’t do unless I read Caplan, as you have).
For example, another reviewer over on Amazon also explained that her attribution of “band wagon jumping” was wrong, but neither their correction or yours helps me judge Caplan at a distance. And you dismiss her due to motivated cognition but it sounds like Caplan is also a parent and so he could be engaged in motivated cognition to defend his laziness. So rather than assume either side is being dumb because someone can invent a just-so story to predict that they would say what they said if they were engaging in motivated cognition, I’d rather just let people talk and then filter the content for evidence and reasoning that’s worth retaining within a personal stock of models and lemmas. I’ve read shpper8424 but I haven’t read Caplan’s book, and so I was hoping that you could do this cognitive work for me :-)
However, it appears to me that you and I have different contextual understandings of shopper8424′ point, so maybe I can spell out the substantive point in her text that I was interested in hearing about. I understood her to simply be pointing out a broad flaw within Caplan’s book: that his advice was massively more specific than was warranted by the evidence he marshaled to support the advice.
For example, she spells out some of Caplan’s particular claims:
She also spells out the justification he uses to support this evidence:
Then she points out that this isn’t very strong evidence, with low sample sizes and no actual power to dismiss any particular set of practices that could account for some of the outcome.
She also offers (admittedly without citation and mixed with stuff that appears suspicious to me) alternative studies that could fill in some of the causal gap between human genetic variations and “everything we observe about human outcomes”:
An argument against shopper8424 that doesn’t help me at all would be that “She doesn’t want to believe that her efforts have been in vain” and “most of the criticism I’ve seen has been from ideologically opposed people”.
A good argument against her, that would be quite helpful would be that Caplan’s book only mentions the twin studies as being consistent with his general advice, and also provides specific studies that how neither diet nor media habits substantively affecting human efficacy outcomes. Maybe he could also report that it doesn’t help to teach your children to meditate or program computers or read books for pleasure. Maybe he could claim that it doesn’t matter if they have violin lessons versus sitting in their bedroom listening to popular music that glorifies violence and the degradation of women. Maybe they shouldn’t be encouraged to play sports and you shouldn’t waste time ferrying them to soccer games when they’re 11. Maybe it doesn’t matter if you homeschool, versus sending kids to a school with metal detectors and class sizes of 70, versus sending them to a private Montessori school where they’ll start being able to start building a social network that enables them to navigate the subcultures of the rich and powerful when they are in their 40′s.
To restate my question: Does Caplan talk about details, or just twin studies? Does he give specific advice about “safe ways to slack” and show that this advice doesn’t harm long term outcomes? Does he cherry pick studies to find those that report the most extreme and shocking results (using a study that found heritability of 0.7 instead of 0.35 and not explaining that there was a range of values)?
To restate my question: What content in Caplan’s book can be mustered in response to a counter argument claiming that that heritability studies are weak for giving precise behavioral advice when clear thinking (and maybe even other studies) about the specific details of the advice show that some details matter?
You seem to have wilfully ignored the main point I made, which is this:
See, she is arguing against the twin/adoption studies based on the idea that the remaining environmental influence could be parenting, when Caplan explicitly points out that this isn’t the case. Unshared environment explains remaining variance. That was her sole substantive point (the rest being obviously false ad-homs and claims about some unspecified “other studies”).
Other studies cannot show that a parenting style detail matters without controlling for heritability. People frequently see studies that say (for example) kids who eat junk food are fat as adults, and assume this is due to childhood environment (controlled by parents). In fact, twin studies have shown that heritability for bmi is ~.80, with the remaining variance due mostly to unshared environment.
Now, if you want to dismiss the vast literature twin/adoption studies out of hand due to “confounds” (you haven’t specified), then, go ahead I guess. But you should have very strong reasons, since twin and adoption studies are considered the gold standard by the relevant social scientists.
Yes. It’s a fairly long books, so he discusses may specific examples.
I should also address this, I guess:
I think Caplan would say, you should do those things if you would consider it worth your time even if it doesn’t contribute to adult success for your kids (it probably won’t). If you enjoy classical music, there is a good chance you kid will as well. He’s mostly against dragging your kid to “enriching” things or stressing out because your kid likes rap.
I appreciated this line. It communicated something substantive about Caplan’s opinions and the amount of evidence for them that I can expect to find in his book. Thank you.
In the meantime, I don’t think twin studies should be entirely dismissed, I just don’t think they explain as much, or can be safely used in the ways they are typically deployed in second order analysis. If you are interested in understanding my concerns here, the Shalizi link from my first attempt to communicate with you (the one that’s been voted down to −1 for reasons I don’t understand) is a good source. I didn’t repeat the points because I thought you (and anyone else who was interested) would be able to follow that link and understand the relevance without clogging up the thread with extraneous details.
The Nurture Assumption is another well done book on this subject.