Wednesday, July 11, 2012

IQ and fertility cross-nationally

I like finding big correlations, but not this time. The cross-national correlation between mean IQ and the total fertility rate for 178 countries is -.72. That's huge. The world gets dumber with each passing day.

26 comments:

Anonymous said...

When will we stop feeding them and send birth control instead?

Anonymous said...

Long-term, you can probably only have greater intelligence and higher fertility in naturally challenging and hostile hunter-gatherer environments - like the North or oceans or something.

Once you have agriculture and industry in a settled, non-hunter-gatherer environment, there seems to be too much incentive for greater intelligence to exploit large amounts of lower intelligence labor that end up with higher fertility rates.

Thomas Hobbes said...

And what happens when the higher intelligence cohort continues to invent machines that leave nothing for the lower orders to do?

Anonymous said...

What makes you think the "higher intelligence cohort" in advanced, agricultural/industrial, settled, non-hunter-gatherer environments consists of inventors over the long-term? Isaac Newton died a virgin. The Wright Brothers didn't have any kids. Tesla was childless.

Artur said...

Thanks for the data.

Would you pls consider blogrolling and/or following us over at :

crimesofthetimes.com ?

Thanks,

- Artur

Dan Haggard said...

As I understand it - insofar as intelligence is genetically determined - it's a non-additive trait. Thus intelligence tends to regress to the mean. Two smart people will tend to have slightly less intelligent kids, and two dumb people will tend to have slightly more intelligent kids.

Stephen said...

Presumably IQ was curving up until it started to curve downward.

Is there data that hints at the year that happened?

Jason Malloy said...

I'm only eyeballing the data in the World Values Survey, but there don't seem to be nations where more educated people have more children. For example (to take one rapidly expanding population), the most educated 25% of Nigerians in the WVS actually exhibit sub-replacement fertility, and have less than half the number of children as the least educated 40%.

Education and IQ have roughly the same relationship in developing and developed nations. So the national level comparisons aren't even sufficient: the lower IQ people in lower IQ nations are having more of the babies.

Anonymous said...

Send contraception instead of food.

I wonder why the social engineers don't come up with some plausible reason to give money to those who get sterilized after they have two kids with a bigger reward for only having one.

Didn't they used to do that?

Ron Guhname said...

"I'm only eyeballing the data in the World Values Survey, but there don't seem to be nations where more educated people have more children. For example (to take one rapidly expanding population), the most educated 25% of Nigerians in the WVS actually exhibit sub-replacement fertility, and have less than half the number of children as the least educated 40%."

It puts a smile one my face when I find myself on the same wavelength as Jason Malloy--this was going to be my next post!

Anonymous said...

So the national level comparisons aren't even sufficient: the lower IQ people in lower IQ nations are having more of the babies.

Dumb and Dumber.

Dan said...

We also know that death rate is inversely proportional to IQ, both between nations and among individuals within nations.

http://mentalhealthupdate.blogspot.com/2009/08/iq-and-mortality.html

http://www.psy.ed.ac.uk/people/iand/Batty%20(2009)%20Epidemiology%20iq%20death%20million%20swedes.pdf

http://en.wikipedia.org/wiki/List_of_countries_by_life_expectancy

The correlation between national IQ and life expectancy is very strong. Also, though there isn't a huge difference in survival rates by IQ for a very rich country, I imagine that the difference in a poor country is much larger.

Dan said...

If you looked only at birth rates, things look very dysgenic. If you looked only at death rates, things look very eugenic.

Nobody ever looks at death rates though.

Anonymous said...

the most educated 25% of Nigerians in the WVS actually exhibit sub-replacement fertility, and have less than half the number of children as the least educated 40%.

Somewhat surprising, not because it's implausible (really), but simply because when this topic is usually broached (IQ dysgenics) there's usually a reply along the lines of "Oh, well, that's just the way it is in welfare state land! African still lives in the world of Greg Clark's Farewell to Alms!"...

Anonymous said...

Nobody ever looks at death rates though.

That's because everyone dies.

Death rates don't matter if the deaths don't happen before breeding.

Dan said...

About 20 nations have a life expectancy of around 45. This might correspond to 2/3 having a life expectancy averaging 60 and 1/3 having a life expectancy averaging 15.

Dan said...

I base my estimate on this:

http://www.infoplease.com/ipa/A0005140.html/

In America in 1850 life expectancy at birth was around 40, but for those who reached age 20, the life expectancy was 60. So the biggest death risk was for childhood.

corvinus said...

Idiocracy is prophecy, I tell ya

Anonymous said...

i keep hearing that two smart people will produce a dumber kid, or one that will have an iq closer to the population average. is there any recent scientific evidence for regression to the mean in terms of iq? and if there is, can someone link me to studies demonstrating this fact

Anonymous said...

It's simple, idiots are not attractive to the intelligent.
The brilliant can't apply their intelligence in finding idiots attractive. Similar to one trying to find the scent of a stinky, stench-filled public restroom appealing to the senses.
Only an idiot would attempt to rationalize such justification.

Dan said...

I can hardly see how the first world avoids a broad bond and currency collapse in the next decade. I think it must happen sooner. One *minor* fault of all the models is that they assume yesterday's producers and consumers are no different than those of tomorrow.

It is difficult enough to see how youth of the same intellectual averages can assume the mountains of debt that have been built for them to carry. Given tomorrow's producers aren't shaping up too well in the ability department, a bond and currency collapse seems unavoidable.

The bond / currency collapse (see e.g. USSR, Communist Bloc) is inherently an intensely conservative event (given that the 2012 status quo is intensely leftist) and it is just about baked into the cake in every developed nation on Earth. So cheer up, folks!

Anonymous said...

another stat that correlates, fewer white babies are born everyday and more brown babies are born everyday...hmmm

acommentor said...

>>>quote..
When will we stop feeding them and send birth control instead?

If you are feeding them then you are dumb, not they.

Jim Bowery said...

Haggard, why do you think intelligence is immune to evolution aka shifting of the mean?

Sam Vincente said...

References?

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