Wednesday, January 21, 2009

Billionaires will be boys

The findings of this piece (via Grobstein) are intriguing but I'm not sure how seriously to take them. The claim that this research allegedly supports is that billionaires are likelier to have sons than daughters because it's adaptive from the POV of maximizing grandchildren. But the presentation fails to address what is, to my mind, the obvious question, which is how much of this effect is due to third-world culture. I wish, in particular, that they had a graph showing (a) regional variation, (b) ethnic variation -- I'm very curious to know if the finding is robust if restricted to Jewish or techie billionaires, for example. The Forbes list for 2008 had a rather large number of Arabs, Indians, Russians, and other poor-country rich people who would presumably abort their female offspring. I wonder how much of the effect remains when you restrict yourself to, say, techie billionaires. Collecting the data is unfortunately quite difficult, but a preliminary look at the obvious suspects -- Bill Gates, Larry Ellison, Steve Ballmer, etc. -- didn't seem to give anything like the 60% male headline number.

6 comments:

Not-a- Generic-User-ID said...

It has been demonstrated that people with less stress / better nutrition skew towards more boys than girls, but my understanding was that this effect was only worth a few percentage points at most. Also, many billionaires got that way through high stress jobs.

I once encountered an interesting article that pointed out that hedge fund millionaires tended to have more daughters than sons and attributed this to the above effect and the high stress nature of the job.

Zed said...

Yes. The 60% number is large enough that my default hypothesis would be some sort of crude systematic effect, like selective abortions in the 3d world. I don't know if it was ill-advised or disingenuous of them not to publish the regional breakdown, but I'd have to see that to decide how seriously to take the result.

James said...

Also, possibly Orthodox Jewish sex practices make boys more common.

Also, I think Steve Bing may have impregnated Kirk Kerkorian's wife. Bing is either a billionaire or close to it, and Kerkorian is a billionaire many times over. The child was a girl, though.

Also, just for the hell of it.

Grobstein said...

Didn't they only use the US billionaires list? I know that doesn't settle the question, especially because they go on to say that the billionaires have varying residence and citizenship (?), but it may limit any 3d-world abortion effect.

Zed said...

I think you're misreading (though I'm not sure). They used the Forbes list of "US$ billionaires," which means people with more than a billion US dollars, not Americans with more than a billion dollars. They claim to have controlled for residence but since they didn't publish the graph and I can't reconstruct it, I don't know what it means for their results.

Grobstein said...

Yes, you are right. Too bad.