Overcoming Bias

Is She Just Friendly?

Men often have trouble knowing what women want.  In particular, men have trouble telling if a women is just being friendly or has a more sexual interest.  This is often blamed on male overconfidence and lack of empathy, but taken together two new papers from the April Psychological Science suggest otherwise.  One paper suggests that people with more empathy can only better read the emotions of those who are trying to be read:

We found that perceivers' trait affective empathy was unrelated to empathic accuracy unless targets' trait expressivity was taken into account: Perceivers' trait affective empathy predicted accuracy only for expressive targets. These data suggest that perceivers' self-reported affective empathy can indeed predict their empathic accuracy, but only when targets' expressivity allows their thoughts and feelings to be read.

The other paper says men are not so much biased as clueless about female sexual intent:

Men perceive more sexual intent in women's behavior than women perceive or report intending to convey. ... We found no evidence that men have lenient thresholds for perceiving women's nonverbal behavior as indicating sexual interest. Rather, gender differences were captured by a relative perceptual insensitivity among men. Just as in previous studies, men were more likely than women to misperceive friendliness as sexual interest, but they also were quite likely to misperceive sexual interest as friendliness.

Maybe, just maybe, most women do not want men and others to read their intent.

Kids, Parents Disagree on Spouses

Monday's Post:

Do young people and their parents really disagree about the qualities of a suitable mate? ... A study involving Dutch, American and Kurdish students ... found that the cliche is, in fact, true. Young Americans told the researchers that qualities they would find unappealing in a potential mate included low intelligence and physical unattractiveness. But they said their parents would object to a mate who was of a different ethnicity, was poor or lacked a good family background.

The responses of Dutch and Kurdish students were similar in that young people invariably considered the potential mate's attractiveness the most important quality, whereas parents uniformly paid more attention to the suitors' social background or group affiliation -- race, religious background and social class.

[The authors] said the consistency of the conflict across cultures suggests the hand of evolution: Parents and offspring ... genetic self-interests, while overlapping, are not identical. The reason young people care so much about intellectual and physical attractiveness, the scientists suggested, is that these characteristics are markers of genetic fitness. By contrast, they said, parents care about group affiliations because parents are primarily interested in whether an incoming member of the family is likely to make a good parent -- and a good all-around team player.

There should indeed be some conflict between kids and parents on suitable spouses, but the size of the conflict seems surprisingly large - do parent and kid genetic interests really diverge that much?   Here's a graphic showing huge differences:

Is Love Something More?

A recent Time cover story swallows evolutionary psychology wholesale:

Losing our faculties over a matter like sex ought not to make much sense for a species like ours that relies on its wits. A savanna full of predators, after all, was not a place to get distracted. But the lure of losing our faculties is one of the things that makes sex thrilling--and one of the very things that keeps the species going. As far as your genes are concerned, your principal job while you're alive is to conceive offspring, bring them to adulthood and then obligingly die so you don't consume resources better spent on the young. Anything that encourages you to breed now and breed plenty gets that job done.

The Greatest Gift, The Best Exercise

In this generous season, consider the greatest gift we regularly and personally give (even if we do not intend it as such): sex.  Back in 2005, Tyler Cowen pondered Michael Vassar's pregnant observation: "there is an inexplicable shortage of sex."  This remains, I think, one of the most neglected questions in social science.  We should devote far more effort to diagnosing and fixing this problem.  To inspire more precious gift-giving, let us review the health benefits of sex [as of 2003]:

Saving yourself" before the big game, the big business deal, the big hoedown or the big bakeoff ... there's no evidence it sharpens your competitive edge. The best that modern science can say for sexual abstinence is that it's harmless when practiced in moderation.

In one of the most credible studies ... tracked the mortality of about 1,000 middle-aged men over the course of a decade. ... Its findings, published in 1997 in the British Medical Journal, were that men who reported the highest frequency of orgasm enjoyed a death rate half that of the laggards. ... In a 2001 follow-on ... by having sex three or more times a week, men reduced their risk of heart attack or stroke by half.

Sex, if nothing else, is exercise. A vigorous bout burns some 200 calories--about the same as running 15 minutes on a treadmill or playing a spirited game of squash. ... Sex also boosts production of testosterone, which leads to stronger bones and muscles. ...

A 2002 study of 293 women ... reported that sexually active participants whose male partners did not use condoms were less subject to depression than those whose partners did. One theory of causality: Prostoglandin, a hormone found only in semen, may be absorbed in the female genital tract. ...

Marriage Futures

After a couple announce their engagement, but before they tie the knot, talk among friends and family often turns to how long the marriage will last.  When folks are not optimistic, they may wonder if they should tell the couple.  But they usually say nothing, depriving the couple of crucial signals to reconsider.

Imagine a web site where you could start a market to bet on the duration of any upcoming or current marriage.  That is, you could buy or sell assets that pay in proportion to the number of years the marriage will last, if it begins, up to some maximum of say fifty years.  If the marriage never starts, you get your money back. 

Once it became widely known that such market prices are often available, wedding guests and the couple would probably check out the price before the wedding, coordinating everyone's expectations about the marriage.   

Added 27Oct: You can estimate marriages here just for fun, and Ravages made a similar betting suggestion. 

Why Not Dating Coaches?

From the New York Times last week:

"We have business coaches, dietitians, accountants, but we don't have an expert for our love life?" said Lisa Clampitt, a dating coach and a founder of the Matchmaking Institute, which trains matchmakers in Manhattan. "It doesn't make sense. It is really the single most important aspect in our life."

Ezra Klein adds:

The idea that folks who need a bit of coaching or advice on these matters are painted as pathetic and weird has always struck me as deeply unfair. This idea that our romantic lives should be organic and spontaneous is rather nice, but for some folks, quite unlikely, and for others, quite self-deceptive. ... That society suggests those who haven't had free guides or good luck should be too ashamed to seek outside help is pretty cruel.

Lies About Sex

Over at Certain Doubts, Gregory Wheeler reviews our lies about sex:

In survey after survey within country after country men report having more heterosexual partners over their lifetime than women do, and as this article and this clarification point out, what people say in these surveys cannot be a reflection of what they do.

If these surveys were representative, we would expect that the average number of heterosexual partners reported by men in each sample to approximate the average number reported by women. Instead, the numbers aren't even close. In Britain men report having an average of 12.7 hetrosexual partners over a lifetime whereas women report an average of 6.5; in France men report an average of 11.6 heterosexual partners, women 4.4; and in Germany men say 15.5, women 10.1.  ...

But the interesting feature of Brown's study was that he also asked the respondents to rate the truthfulness of their estimates. He found that 5% of men and 4% of women indicated that they thought their estimates were inaccurate, and 16% of men and 11% of women indicated that they knowingly misrepresented their counts. Still, even when these "self-incriminators" were removed from the sample population, there was still a significant discrepancy between the counts for men and women.

Yes, many are aware they lie about sex.  But it seems many others are not aware.  That suggests that you, yes you, do not really know how many sexual partners you have had!

Added: The movie Secrets and Lies has an ambiguous case: does she lie or self-deceive?

Is Hybrid Vigor IQ Warm And Fuzzy?

The July 2007 Psychological Review has Michael Mingroni reviewing an interesting theory he published in Intelligence in 2004, that IQ has increased mainly because of more interracial and cross-cultural mating:

IQ test scores have risen steadily across the industrialized world ever since such tests were first widely administered, a phenomenon known as the Flynn effect. Although the effect was documented more than 2 decades ago, there is currently no generally agreed-on explanation for it. The author argues that the phenomenon heterosis represents the most likely cause. Heterosis, often referred to as hybrid vigor, is a genetic effect that results from matings between members of genetically distinct subpopulations, such as has been occurring in human populations through the breakup of small, relatively isolated communities owing to urbanization and greater population mobility.

Regardless of whether Mingroni's theory is true, I find it striking that it seems less politically correct than it could be. 

The first response you often hear to genetic explanations of IQ, or even the very idea of IQ, is that such ideas encourage racists, such as Nazis.  But Mingroni's hybrid vigor theory seems tailor-made to oppose racist and other xenophobic mating policies; instead of killing off "lower" races or preventing interracial mating, Mingroni's theory suggests one wants to encourage diverse mating and preserve other races as sources of genetic diversity. 

The currently political correct environmental explanations of IQ, in contrast, are quite compatible with racist and other xenophobic mating policies.  That is, one can nearly as easily oppose contact and mating with outsiders for fear of contamination from outsiders' cultural and other environmental influences, as from outsiders' genes.  Such arguments were offered in the recent immigration debate, for example.  So why are environmental IQ theories so praised for opposing racism, relative to hybrid vigor?   

Food Vs. Sex Charity

Scott Aaronson asks a great question: 

Consider two men, A and B. Man A steals food because he’s starving to death, while Man B commits a rape because no woman will agree to have sex with him.  From a Darwinian perspective, the two cases seem exactly analogous. In both we have a man on the brink of genetic oblivion, who commandeers something that isn’t his in order to give his genes a chance of survival. And yet the two men strike just about everyone — including me — as inhabiting completely different moral universes. The first man earns only our pity. We ask: what was wrong with the society this poor fellow inhabited, such that he had no choice but to steal? The second man earns our withering contempt.

One problem with the question is that in our society giving enough sex to satisfy is expensive, while giving enough food to satisfy is cheap.  So it might help to imagine a society where the person who lost the food was also in some, though less, danger of starving.   

But even then food and sex seem to be treated differently.  When we give food aid we don't just give rice and beans to keep folks from starving; we give them enough to have a moderately tasty diet.   We do nothing remotely similar for sex.

To me the obvious answer is that our concern about inequality is not very general - compared to inequality in access to food, humans are just not that concerned about sexual inequality, especially for men.  Presumably for our ancestors, the gene pool of a tribe could benefit from equalizing food in ways that it could not benefit by equalizing sex. 

Added: Riffing off this post, Scott rewords his question:  Why do we, as a society, provide food stamps for the hungry but not sex stamps for the celibate?

7/7/07 Weddings

From Time.com:  "Superstitious Americans...have gone to great lengths to secure the triple sevens as their wedding date, hoping the lucky numbers will make them lucky in love...It may well be the most popular wedding day in history."

Since the demand for weddings on this date was high, the price for 7/7/07 weddings should also have been high compared to other dates.  Thus, only couples willing to pay a superstitious premium got married on 7/7/07.  This could provide a great research opportunity.  Are superstitious couples, for example, more likely to get divorced?  Do they make as intelligent financial decisions as other couples do?