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Comment author: satt 14 July 2014 01:21:35AM *  3 points [-]

Since I have very little expertise in these areas, I was just wondering if anyone knew about efforts to estimate the impact of these confounders and adjust for them.

One way to assess the confounders' impact is to estimate heritability using a method that doesn't rely on making assumptions about adoptees or twins, and see whether it gives higher/lower results. Here's a paper that did so to estimate height's heritability in a sample of 3,375 sibling pairs:

I'd personally delete the first two words from that paper's title, but it nonetheless avoided whatever issues there might be with using adoptees & twins, getting a heritability estimate of 80% (with a 95% confidence interval of 46% to 85%), broadly comparable to those from older twin studies.

Comment author: Stuart_Armstrong 14 July 2014 09:26:17AM 1 point [-]

Thanks! I still think they're overconfident at having solved the problem, but it's a useful piece of the puzzle.

Comment author: gwern 13 July 2014 03:13:41AM 7 points [-]

This is a standard criticism of the twin studies. For example, Shalizi http://vserver1.cscs.lsa.umich.edu/~crshalizi/weblog/520.html

I will quote from an old paper by Bronfenbrenner [3, pp. 159--160], because it's handy and it makes the point:

The importance of degree of environmental variation in influencing the correlation between identical twins reared apart, and hence the estimate of heritability based on this statistic, is revealed by the following examples.

a. Among 35 pairs of separated twins for whom information was available about the community in which they lived, the correlation in Binet IQ for those raised in the same town was .83; for those brought up in different towns, the figure was .67.

b. In another sample of 38 separated twins, tested with a combination of verbal and non-verbal intelligence scales, the correlation for those attending the same school in the same town was .87; for those attending schools in different towns, the coefficient was .66. In the same sample, separated twins raised by relatives showed a correlation of .82; for those brought up by unrelated persons, the coefficient was .63.

c. When the communities in the preceding sample were classified as similar vs. dissimilar on the basis of size and economic base (e.g. mining vs. agricultural), the correlation for separated twins living in similar communities was .86; for those residing in dissimilar localities the coefficient was .26.

d. In the Newman, Holzinger, and Freeman study, ratings are reported of the degree of similarity between the environments into which the twins were separated. When these ratings were divided at the median, the twins reared in the more similar environments showed a correlation of .91 between their IQ's; for those brought up in less similar environments, the coefficient was .42.

(Let us pause a moment to contemplate the sense in which identical twins, growing up in the same town and attending the same school, are "raised apart".)

Comment author: Stuart_Armstrong 13 July 2014 07:41:53AM 1 point [-]

Thanks! That's yet another problem - but few solutions!

[Question] Adoption and twin studies confounders

4 Stuart_Armstrong 11 July 2014 04:44PM

Adoption and twin studies are very important for determining the impact of genes versus environment in the modern world (and hence the likely impact of various interventions). Other types of studies tend to show larger effects for some types of latter interventions, but these studies are seen as dubious, as they may fail to adjust for various confounders (eg families with more books also have more educated parents).

But adoption studies have their own confounders. The biggest ones are that in many countries, the genetic parents have a role in choosing the adoptive parents. Add the fact that adoptive parents also choose their adopted children, and that various social workers and others have great influence over the process, this would seem a huge confounder interfering with the results.

This paper also mentions a confounder for some types of twin studies, such as identical versus fraternal twins. They point out that identical twins in the same family will typically get a much greater shared environment than fraternal twins, because people will treat them much more similarly. This is to my mind quite a weak point, but it is an issue nonetheless.

Since I have very little expertise in these areas, I was just wondering if anyone knew about efforts to estimate the impact of these confounders and adjust for them.

Comment author: Kaj_Sotala 09 July 2014 12:10:38PM 0 points [-]

What's the outsider feedback on those been like?

Comment author: Stuart_Armstrong 09 July 2014 12:22:06PM 0 points [-]

Quite positive, but scarce.

Comment author: mwengler 08 July 2014 11:42:54PM 9 points [-]

What are your current beliefs on climate change? Specifically, would you defer to the view that greenhouse gas forcing is the main source of long-term climate change? How long-term? Would you defer to the IPCC range for climate sensitivity estimates?

Based on asking UCSD scientists when I've met them at parties, I'd parrot them and say human emissions are maybe about 1/2 of the source of long term climate change. I would not defer to the IPCC or to anybody without giving them careful reads. The issue is too politicized to trust anyone merely because of fancy or scientific sounding titles.

What were your beliefs on climate change when you first came across the subject, and how did your views evolve (if at all) on further reading (if you did any)? (Obviously, your initial views wouldn't have included beliefs about terms like "greenhouse gas forcing" or "climate sensitivity").

When I first heard of global warming I thought it was ludicrous because I could remember a number of years ago reading about the coming ice age and all the evidence for that. The idea that we should bring CO2 emissions to a halt is ludicrous to me even in the face of real climate change because there are so many cheaper ways to cool the earth than to stop emitting CO2. The idea that we should stop emitting CO2 because it is emissions of CO2 that got us here is simplistic, and, I suspect, essentially reflecting a religious impulse of "purity," the same kind of thing that leads to strange dietary restrictions and proscriptions against associating with menstruating women. I was very influenced by Michael Crichton (a denier, more or less, but a damn smart one) and I accept the steady stream of obviously real experts who say we have nowhere near enough reason to think that trillion dollar changes like stopping burning fossil fuels is likely to be any more effective than solutions that cost a millionth as much. A good source of these experts is to look at the guests on "econtalk" hosted by Russ Roberts.

What are some surprising things you learned when reading up about climate change that led you to question your beliefs (regardless of whether you changed them)? For instance, perhaps reading about Climategate caused you to critically examine your deference to expert consensus on the issue, but you eventually concluded that the expert consensus was still right.

I was surprised that there is still no measurable ocean level change even as every hurricane or blizzard that passes by is claimed to be a sign of the changes that have already occurred. I was surprised to learn that there are easily worked out things that can be done that could cool the earth at a cost of a few billion US$ or less. I was surprised to learn that glaciers really are melting.

If you read my recent posts linked above, did the posts contain information that was new to you? Did any of this information surprise you? Do you think it's valuable to carry out this sort of exercise in order to better understand the climate change debate?

I started reading them, they seemed OK, just didn't have the energy to get through them at the moment.

other comments

The real question is not "what is really happening" but "what is the best thing to do now." Intelligent study is certainly a thing to do now and fortunately there is no shortage of that, even though the politicization will make it really hard to dig through and find reasonable descriptions of results as they are developed.

I am also fascinated by the idea that a slow rise in sea level is described as a catastrophe. It is not. The sea has always eroded the coast and houses and other structures last a finite time in many of these places. Oh Well. When I suggest that a sea level rise slow enough that "we can walk away from it" is not particularly frightening, I am warned that poor countries with no hills could see millions die... of drowning? It is not clear. The hypothesis is that since they are poor they can't figure out how to move somewhere else. So the solution is to turn off all the engines in the world to help keep Bangladesh above sea level? It would be simpler and cheaper to buy a few million square miles in Africa an pay to move all interested Bangladeshi's there. Oh but that is not politically realistic? But turning off all the engines is?

The usage of fossil fuels has not only NOT declined worldwide, it continues to grow as fast as it has ever grown. No matter at what rate renewable energy comes on line, more fossil fuel energy comes on line faster. " Solving" CO2 by having Americans and Europeans buy Tesla's is like "solving" population growth by having American's and Europeans use condoms. In each case, if you do not change what China, India, and Africa are doing you are for all intents and purposes doing nothing but rendering the US and Europe less important and powerful in the future of earth.

Comment author: Stuart_Armstrong 09 July 2014 10:43:18AM 3 points [-]

I was surprised that there is still no measurable ocean level change

There seems to be: http://en.wikipedia.org/wiki/Current_sea_level_rise

Comment author: Mark_Friedenbach 08 July 2014 06:04:21PM *  1 point [-]

For a very different perspective from both narrow AI and to a lesser extent Goertzel*, you might want to contact Pat Langley. He is taking a Good Old-Fashioned approach to Artificial General Intelligence:


His competing AGI conference series:


  • Goertzel probably approves of all the work Langley does; certainly the reasoning engine of OpenCog is similarly structured. But unlike Langley the OpenCog team thinks there isn't one true path to human-level intelligence, GOFAI or otherwise.

EDIT: Not that I think you shouldn't be talking to Goertzel! In fact I think his CogPrime architecture is the only fully fleshed out AGI design which as specified could reach and surpass human intelligence, and the GOLUM meta-AGI architecture is the only FAI design I know of. My only critique is that certain aspects of it are cutting corners, e.g. the rule-based PLN probabilistic reasoning engine vs an actual Bayes net updating engine a la Pearl et al.

Comment author: Stuart_Armstrong 09 July 2014 09:32:56AM 0 points [-]


Comment author: Stuart_Armstrong 08 July 2014 04:38:47PM 0 points [-]

or at least explain them in ways that intelligent outsiders can understand well enough to criticize

Based on feedback, I think I achieved that through my "Smarter than Us" booklet or through the AI risk executive summary: http://lesswrong.com/lw/k37/ai_risk_new_executive_summary/

Comment author: Stuart_Armstrong 08 July 2014 04:12:46PM 19 points [-]

Based on my appreciation of the scientific method and my research into the weaknesses of models and experts, I take the median IPCC estimate as correct, but assume the uncertainties are greater than they claim. This is somewhat scary, as uncertainties cut in both directions, and moderate climate change is something we can cope with, but extreme climate change is very much worse.

Comment author: drnickbone 08 July 2014 08:35:15AM 2 points [-]

Hmmm... I'll have a go. One response is that the "fully general counter argument" is a true counter argument. You just used a clever rhetorical trick to stop us noticing that.

If what you are calling "efficiency" is not working for you, then you are - ahem - just not being very efficient! More revealingly, you have become fixated on the "forms" of efficiency (the metrics and tick boxes) and have lost track of the substance (adopting methods which take you closer to your true goals, rather than away from them). So you have steelmanned a criticism of formal efficiency, but not of actual efficiency.

Comment author: Stuart_Armstrong 08 July 2014 10:59:23AM 0 points [-]

So you have steelmanned a criticism of formal efficiency, but not of actual efficiency.

Now we're getting somewhere :-)

Comment author: ntroPi 07 July 2014 10:40:51PM 1 point [-]

I actually like this post and agree to most points you make. I'm not talking about the meta points about steelmanning and rhetoric tricks.

The obvious and clearly stated bias helped me to better insights than most articles that claim true understanding of anything.

I'm not sure whether this is due to increased attention to weak arguments or a greater freedom to ignore weak arguments as they are probably not serious anyways.

Can it be both? Was that effect intentional?

I would read a "Steelmanning counterintuitive claim X" series.

Comment author: Stuart_Armstrong 08 July 2014 07:18:47AM 0 points [-]

Interesting. Glad it seems to have given some new understanding!

But please believe me, though a lot of the individual points are very valid, I could shred my central thesis entirely.

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