The usual.

I haven’t been able to blog much because of various other responsibilities, but I definitely do feel pent up posting energy. So when I come back I assume that I’ll have a lot of stuff to say. Meanwhile I’m chortling a bit about this bizarre attack on my friend Steve Hsu. Here’s the issue that I always have with this: Steve managed to get tenure as a theoretical physicist. When you’re talking to someone who is an academic theoretical physicist it is generally optimal to not assume a priori that they’re ignorant dullards. Unless that is you want to just engage in empty signalling rhetoric.

Though despite not having concerted time to write, I am tweeting a lot since that requires only minimal lengths of attention. Mostly it’s just repeating the functionality of my Pinboard, though I do comment and what not.

Finally, I keep hearing that the Big Five personality typology is much more scientific than Myers Briggs. So I took a bunch of tests which purport to analyze the Big Five categories.

Extraverted: Very high. Consistent. I was 90-99% on all tests.
Agreeableness: Low. Consistent. Generally in the 15-0% range.
Openness: Medium. This was not very consistent. 40-60% range.
Neuroticism: Erratic. For whatever reason I varied from 20-80% here.
Conscientiousness: Medium. But there was some variation.

Oh, and here’s a list of books I’ve rated for Good Reads.

(via The Festival of Patience)

The above figure displays results from males in the General Social Survey who answer yes to the proposition that they’ve watched a pornographic film over the past year. This fact was cited in my post Porn, rape, and a ‘natural experiment’, to disabuse people of the notion that porn consumption has increased radically the past generation. I was aware of this finding, and so generally am careful to focus on the quantity of porn consumed, rather than the social penetration of porn consumption. No matter what the “survey says,” the IT sector is quite aware of the fact that pornographic material is a very high fraction of internet traffic (e.g., more people check Pornhub than BBC).

But I am not sure sure we should trust the GSS results any more at this point. I did some cursory poking around and last month there was a large sample size survey of Dutch youth to investigate the effects of porn consumption, Does Viewing Explain Doing? Assessing the Association Between Sexually Explicit Materials Use and Sexual Behaviors in a Large Sample of Dutch Adolescents and Young Adults:

The study found that 88% of men and 45% of women had consumed SEM [“sexually explicit material”] in the past 12 months. Using hierarchical multiple regression analyses to control for other factors, the association between SEM consumption and a variety of sexual behaviors was found to be significant, accounting for between 0.3% and 4% of the total explained variance in investigated sexual behaviors.

How the sample was collected is important for generalization, so I want to reproduce that part of the method in case you don’t have access:

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Standard apologies that I have had not the marginal time to blog much, but I thought it was important that I least note that Dr. Peter Ralph and Dr. Graham Coop’s paper on identity-by-descent segments and European populations and history is out in its final form in PLoS Biology, The Geography of Recent Genetic Ancestry across Europe. I’ve been familiar with the outlines of these results for about a year now, and to be frank I am still digesting them. The media hype will come and go, with true but to some extent trivial headlines that “all Europeans are related,” but the consequences of these sorts of genetic inquiries into the relatedness of populations are going to be long lasting. At least they should be.

But before I go on about that, if you find the paper itself a bit daunting (though the main body of the text strikes me as eminently readable for a piece of statistical genetics), see Carl Zimmer’s condensation. With this sort of result there is liable to be confusion, so note that Graham Coop has been posting comments on Carl’s blog (and elsewhere, and you can always send him a note on Twitter). Additionally he has a very readable FAQ out. Dr. Coop told me on Twitter that there would even be updates tomorrow as well! In particular one aspect of the paper which I noticed is that most relatively short, but detectable segments (~10 cM), between any two individuals in many nationalities is not going to be evidence of recent genealogical affinities, but deeper historical process.

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In some quarters it is now “conventional wisdom” that Google Glass is going to seem dorky and laughable at first. But it’s probably just the pre-alpha version of the type of technology which seems inevitable (and is familiar to anyone who has read cyberpunk science fiction).

Last week’s thread was rather informative.

Update: Just to be clear, I think the variation across cultures is probably explained in large part by confusion as to what is being asked, and differential sampling. In particular, I suspect that the ‘Turkey” sample is more representative than the “Bangladesh” sample, because Turkey is a more developed society.

 

I’ve mentioned before that many (most?) Muslims are Creationists, broadly understood. According to Pew’s Religious Landscape Survey 42 percent of American Muslims accept that evolution is the best explanation for the origin of human life on earth. This is roughly in line with the American public, if a touch on the Creationist side. The numbers are similar in Turkey. Also, it must be mentioned that unlike most I have some experience with educated (and scientifically trained) Muslims, and can attest to the fact that many are Creationists (my family).

So the results of a new survey of the world’s Muslims by Pew took me aback a bit, in that it reports widespread acceptance of evolution among Muslims.  To add to the plausibility the results for Turkey are in line with previous findings: a bit more of Turkey’s population are Creationist than not. The results for highly secularized European Muslim populations are plausible, though the gap between Albania and Kosovo is somewhat strange. But look at the results for Bangladesh and Lebanon!

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A few years back I was rather fixated on issues of maternal fetal health. In particular I was worried about gestational diabetes in relation to my wife because I come from an ethnic group with an elevated risk for these sorts of problems, and the effect when you are in mixed-race marriages seems to be additive (i.e., unlike some risk factors associated with pregnancies the mother’s ethnicity is not the only relevant variable). This is embedded in the broader suite of metabolic diseases which exhibit ethnic variation. Early work on genome-wide selection in humans yielded the result that there was a strong enrichment for signals of adaption within regions of the genome associated with metabolism, so this should not be that surprising. Humans are a geographically dispersed species that inhabits a wide range of environments, so natural selection would shape the distribution of phenotypes within populations if evolution is a significant historical process (it is).

A paper in last month’s Trends in Genetics highlights more precisely how natural selection would operate in a life history context in specific cases. Many ways to die, one way to arrive: how selection acts through pregnancy:

When considering selective forces shaping human evolution, the importance of pregnancy to fitness should not be underestimated. Although specific mortality factors may only impact upon a fraction of the population, birth is a funnel through which all individuals must pass. Human pregnancy places exceptional energetic, physical, and immunological demands on the mother to accommodate the needs of the fetus, making the woman more vulnerable during this time-period. Here, we examine how metabolic imbalances, infectious diseases, oxygen deficiency, and nutrient levels in pregnancy can exert selective pressures on women and their unborn offspring. Numerous candidate genes under selection are being revealed by next-generation sequencing, providing the opportunity to study further the relationship between selection and pregnancy. This relationship is important to consider to gain insight into recent human adaptations to unique diets and environments worldwide.

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For old time’s sake. The cats have a new companion….

Update: To be explicit, I’m not claiming that the correlation is causal. Rather, I’m pointing out that the explosion in porn use does not seem to have led to a concomitant explosion in sex crimes, which would have been the prediction by social conservatives and radical feminists if they could have known of the extent of penetration of pornography into culture and private lives over the next 20 years in 1990.

I am almost literally one of the last of the generation of young men for whom the quest for pornography was an adventure. One could say that I had the misfortune of my adolescence overlapping almost perfectly with the last few years prior to the ‘pornographic singularity.’ I speak here of the internet, circa 1995 and later. Prior to this era of the ‘pornographic explosion’ one often had to rely upon a lax or absentee father of a friend, from whom the porn was ‘borrowed,’ and then returned with the owner none the wiser. My youngest brother, who is 15 years my junior, would no doubt find my escapades as a 15 year old bizarre in the extreme (though I believe I did not view video pornography until I was 16). In fact, I recall realizing that something radical had occurred when visiting my family and observing my brother, who was 8 at the time, deleting porn spam from his Hotmail account. Porn as nuisance rather than treasure would have amazed my adolescent self.

It seems plausible that the generation after 1995 has witnessed levels of aggregate porn consumption orders of magnitude greater than that before 1995. This is a massive natural social experiment. As with any social experiment you have anecdata-driven ‘moral panic’ pieces in the press which don’t seem to align well with what you see in the world at large. Mo Costandi pointed me today to one such piece about porn ‘re-wiring’ the brains of young boys and making them sexually dysfunctional. Standard stuff. On Twitter I pointed out to Mo semi-seriously that actually crime had declined since widespread pornographic consumption in the mid-1990s. Quite reasonably Mo inquired specifically about sex crimes. Fair enough. As it happens the FBI has records of ‘forcible rapes’ reported to the police in the USA going back to 1960.

Here they are in absolute numbers:

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