Comments on: A world full of children

By: DK

DK — Tue, 02 Aug 2011 04:21:16 +0000

Bob is absolutely right. The regression shown is completely bogus. This is scientific equivalent of Hollywood’s “zoom on a low res picture, apply Computer Magic (TM) and get very high res detail back”. LOESS-shmoess. However this line was generated and never mind what smoothing parameters were used, it’s still bogus in that one cannot derive conclusions from its shape the way the author does – there simply isn’t enough data! (The actual paper does not even mention how the line was drawn nor it has anything remotely resembling materials and methods; it does have completely uninformative huge photograph though. I guess different fields have different standards…)

By: Razib Khan

Razib Khan — Sun, 31 Jul 2011 16:14:45 +0000

#4, if you think LOESS is hand-drawn you should shut up otherwise i might finally make u.

#1, yeah, he elaborates on this. he assumes a malthusian ‘balance.’

#2, i assume cave burial grounds or whatever are being substituted.

By: Ian

Ian — Sun, 31 Jul 2011 13:29:27 +0000

@4 – looks like a LOESS regression. I haven’t looked at the original paper, but I rather doubt it’s “bogus”. The pre-Neolithic data is a little thin, but just eyeballing it, there looks to be a trend over the first 1000 years of agriculture.

By: bob sykes

bob sykes — Sun, 31 Jul 2011 11:56:41 +0000

I don’t see it. The (hand-drawn?) line is bogus. Take it out and look at the data. There is no trend.

There does seem to be an increase in cemeteries during the neolithic, which makes sense if there are more people around. However since the writers adjusted time to coincide with the start of the local neolithic there could be an error there, too. That is, if they are wrong about the start of the local neolithic, cemeteries might plot left or right of where the chart shows them.

By: Justin Giancola

Justin Giancola — Sun, 31 Jul 2011 09:59:50 +0000

both good points.

By: Peter Ellis

Peter Ellis — Sun, 31 Jul 2011 08:41:58 +0000

Do mobile hunter-gatherers even have cemeteries, generally? If not, then what evidence are they using for the points they have before the transition?

By: OmegaMom

OmegaMom — Sun, 31 Jul 2011 08:00:05 +0000

Okay…I’m curious. Doesn’t it point not necessarily to a higher proportion of 5-19-year-olds overall, but a higher proportion of *dead* 5-19-year-olds? In other words, this seems to point to an agrarian society being much more dangerous to young humans than the earlier hunter-gatherer societies. I’m thinking more in terms of higher population density leading to more growth of disease that takes down younglings without fully grown immune systems. ?