Quantity or quality parenting time

I follow the scientific evidence on parenting practices, and the sad fact is that there is barely any evidence for some practices being better than others. Nearly all parents believe that their nurturing is making a positive difference, but we cannot prove it, so the difference is almost surely a lot less than you think.

Here is the latest, from economist Justin Wolfers in the NY Times:

The latest salvo in the mommy wars is that all that time you spend parenting just doesn’t matter. But it’s a claim that, despite the enthusiastic and widespread coverage by news media outlets that include The Washington Post, Vox, The Guardian, The Independent, The Globe and Mail, NBC News, The Chicago Tribune and The New York Times’s Motherlode, does not hold water.

The claim that parenting time doesn’t matter is the bottom line of a single recent study by a team of sociologists who suggest that child outcomes are barely correlated with the time that parents spend with their children. It’s essentially a nonfinding, in that they failed to find correlations that could be reliably discerned from chance.
This nonfinding largely reflects the failure of the authors to accurately measure parental input.

Wolfers hires a high-end nanny to take care of his kids, so he is convinced that the extra money is worth it.

This study has been reported as reassurance to moms that quality time can substitute for quantity time.

His main complaint is that the study used statistical sampling. Of course all the other social science studies do also. Wolfers is just an economist, and not an expert on child-rearing.

This is why most high-quality studies of parenting time focus instead on how often parents read to their children, play with them or help them with homework over a period of a month or longer — long enough to represent their different approaches to parenting.

Those high-quality studies have never been able to show any benefit for parents reading to kids or helping with homework.

For the evidence that nurturing is irrelevant, see the book, The Nuture Assumption. excerpted here and discussed on PBS TV.

For evidence that genetic influences are much more important, see JayMan.

In animal studies, it has been noted that some species invest a lot of resources into a small number of offspring (K-selection), and others just produce as many offspring as they can (r-selection). You see these differences in people also. This is quality v. quantity again.

These trade-offs now are a lot different than for primitive societies. Today almost all kids get enuf nutrition, care, and schooling to become prosperous adults. Rich families prefer to have very few kids, and to spend a lot of money on nannies and private schools. It is debatable whether all that money is of any significant long-term benefit to the kids. As JayMan explains, the major influences appear to be genes, then maybe the external non-family environment, and then random unexplained factors.

Parents are more eager than ever to get their kids into an elite college and pay immense tuitions, but NY Times columnist Frank Bruni has a book out on how this is all a foolish waste.

Razib Khan also cites The Nuture Assumption, and writes:

But one thing bothers me about these treatments in the press: the totally confounded nature of causality. Consider:

The one key instance Milkie and her co-authors found where the quantity of time parents spend does indeed matter is during adolescence: The more time a teen spends engaged with their mother, the fewer instances of delinquent behavior. And the more time teens spend with both their parents together in family time, such as during meals, the less likely they are to abuse drugs and alcohol and engage in other risky or illegal behavior. They also achieve higher math scores.

The implication above is that “time engaged with mother” → “less delinquent behavior.” But we don’t know that that’s causal at all. Rather, it could be a correlation between a third factor, term in “prosociality,” and these two variables. More generally if you look for references to genetics in the original paper you won’t find it. It strikes me that one of the reasons that parental investment doesn’t seem to matter so much is that there are many outcomes they just aren’t effecting, because their primary contribution in heritable, with a major secondary contribution to the environmental context in which children grow up (the “non-shared environment”).

Yes, the causality is probably backwards. The lesser dilinquent personality is causing the greater engagement with the mother.


Update: The Dilbert cartoonist has some sensible comments, and a link to the original study:

Today I read an opinion that I didn’t understand, criticizing the media for not understanding a study. So I read that study. I didn’t understand it. And I still have an opinion. Because this is the Internet, damn it.

The topic of the study is whether or not the amount of time a mother spends with a kid matters to the outcome. Seems important to know, right?

Maybe not.

It might be better NOT knowing the truth in this case. Because the truth is about an average. And no individual is average.

If you tell mothers that the average mom does X to get a good result, peer pressure causes all moms to do X, or to feel guilty for not. Even if it kills the kid. Music lessons are a valuable learning experience for some kids and torture for others.

What are the odds that one flavor of parenting will be the right fit for every culture, every kid, every parent, and every situation? I’m going to say zero.

Let’s try this experiment: If your kids are well-behaved and mine are not, let’s switch kids for a month and see what happens. Will your awesome parenting fix them? Good luck with that, sucker!

The sameness illusion is what makes most management fads start out smart and morph into pure ridiculousness. The thing that worked for Apple is not necessarily going to work for… well, anyone else.

Career advice has the same limitation. I could tell you every trick I used to become a famous cartoonist but it would not help you become one. You and I are different people in different times and different circumstances. Your strategy needs to be crafted for your situation.

I am a big believer in scientific research, and we have some legitimate resarch on parenting methods. But most of it is nearly worthless for giving practical advice to parents.