The future of fertility; more kids please

By Razib Khan | June 22, 2010 10:52 am

After my post yesterday on Bryan Caplan’s argument for having more children, I was curious as to what the public perceptions of the ideal number of children was in the General Social Survey. There’s a variable with large N’s which is already in there: CHLDIDEL. It asks:

What do you think is the ideal number of children for a
family to have?

Curiously I noticed a bounce back in terms of ideal numbers in the 2000s plotting CHLDIDEL by year, YEAR. This could be just due to demographic changes (a larger proportion of pro-natalist immigrants after 1965), so I sliced the sample in a few different ways. More specifically, I focused on women aged 18-40, since these are presumably the ones who are the ultimate agents in terms of family size, and combined years by decade to increase sample size for the demographic slices.

It does seem that there was a broad societal shift among women of child-bearing age to prefer larger families in the 2000s in relation to the previous decade. Below the fold I have some charts with the means (the small dots) by decade as well as the 95% confidence interval for various demographics.







One of the two reasons that Thomas Malthus and David Ricardo were wrong about the future economic equilibrium, at least over the medium term, is that in the 19th century industrializing nations began to go through demographic transitions. But there is no reason that this need to persist eternally, and one presumes that over time there will be some shift back toward pro-natalism because by tautology those who are by disposition or ideology toward favoring procreation will propagate their genes and memes to a greater extent into the future.

CATEGORIZED UNDER: Culture, Data Analysis, GSS
  • Meg

    I don’t suppose we could get the y-axes of the charts on the same scale? That would make it easier to judge relative numbers between demographic groups.

  • Razib Khan

    there’s nothing surprising in the between group comparisons. the ones you’d expect want more kids, do so. in fact there’s less difference than i would have thought.

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  • Markk

    That is an amazing change in all the groups. What has the real birthrate done in those groups though?
    Is this a longing for something that isn’t done as much anymore?

  • Tom Bri

    Speaking personally, I would love to have had 5, like my folks, and my brother. But I married late, and my wife thought 40 was too old to have another. Kids are great.

    In spite of peoples’ stated desires, if late marriage continues to increase, family size won’t, barring great improvements in medical interventions.

  • Clark

    That’s a good point Tom.

    I also wonder if happiness measures get at instabilities added by kids. i.e. kids get sick more, causing more bills, leading to financial insecurity. If you roll the dice and don’t get those situations then you may be much more happy but if you are unlucky it can create much more added stress. That kind of variance seems hard to measure with the way these things are asked without larger samples and deeper correlations.

    I just had kid #3 two weeks ago. So I’m above replacement now.

  • Razib Khan

    congratulations clark! battling the idiocracy one child at a time :-)

  • pconroy

    because by tautology those who are by disposition or ideology toward favoring procreation will propagate their genes and memes to a greater extent into the future.

    This is exactly what I argued a month or so ago on FeministX’s blog.

    I would also add, that women who do forgo childbearing till later years, are “selecting” ova who age well, and so are also selecting for later childbearing in their descendants, right?!

    So over time, not a lot to worry about.

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  • Chris T

    There is some evidence that low fertility is a transient phenomena between low and high human development:


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About Razib Khan

I have degrees in biology and biochemistry, a passion for genetics, history, and philosophy, and shrimp is my favorite food. In relation to nationality I'm a American Northwesterner, in politics I'm a reactionary, and as for religion I have none (I'm an atheist). If you want to know more, see the links at


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