razib | November 1, 2008My discussion with Jim Manzi on epistasis generated a lot commentary. It's a complex topic, as I said there are different ways to define epistasis, and evolutionarily its effect on trait value might be different from its effect on fitness. Finally, I think it is important that epistatic and additive genetic variation can convert from one to the other; and over the long term it is this heritable variation which is the "stuff of evolution," so to speak. But a friend recommended that I post a figure from Genome-wide association analysis identifies 20 loci that influence adult height.
One…
razib | October 31, 2008Genetic and Linguistic Coevolution in Northern Island Melanesia:
...Here, we use high-quality data and novel methods to test two models of genetic and linguistic coevolution in Northern Island Melanesia, a region known for its complex history and remarkable biological and linguistic diversity. The first model predicts that congruent genetic and linguistic trees formed following serial population splits and isolation that occurred early in the settlement history of the region. The second model emphasizes the role of post-settlement exchange among neighboring groups in determining genetic and…
razib | October 31, 2008I have a piece up for The Guardian's new Comment is Free Belief site, The use and abuse of statistics - Prophecies of the extinction of religion, or its triumph, fall prey to the weaknesses of linear prediction. Implicit in my argument are these sorts of dynamics:
Bearman and Brückner have also identified a peculiar dilemma: in some schools, if too many teens pledge, the effort basically collapses. Pledgers apparently gather strength from the sense that they are an embattled minority; once their numbers exceed thirty per cent, and proclaimed chastity becomes the norm, that special identity…
razib | October 31, 2008The Political Gender Gap: Gender Bias in Facial Inferences that Predict Voting Behavior:
...Contrary to the notion that people use deliberate, rational strategies when deciding whom to vote for in major political elections, research indicates that people use shallow decision heuristics, such as impressions of competence solely from a candidate's facial appearance, when deciding whom to vote for. Because gender has previously been shown to affect a number of inferences made from the face, here we investigated the hypothesis that gender of both voter and candidate affects the kinds of facial…
razib | October 30, 2008Dienekes and Kambiz both hit a new paper which claims to find the Y chromosomal (direct male descent lines) signatures of the ancient Phoenician colonization of the Mediterranean. I tend to see a lot of merit in Dienekes' criticisms, the net here is thrown so wide that it's almost one of those models where it explains everything so that it explains nothing. Compare this to the recent work on the genetics of the Etruscans and modern populations of Tuscany, which strongly lend credence to ancient myths of their origin in Anatolia The historical data I've seen suggests that both the Phoenician…
razib | October 30, 2008Jim Manzi has a long post up on epistasis, that is, gene-gene interactions:
We could call this process of competing algorithms struggling to find the best solution as fast as possible "meta-evolution". That is, each potential search method must compete for survival. The fact that the algorithm that has won this (idealized) competition in the real world has the form of a GA seems to indicate that there is some structure to the relationship between gene vectors and physical outcomes, but that it is much more complex that simple linear combinations without interaction terms, otherwise nature…
razib | October 30, 2008You can read all about it. I don't have anything interesting to say on the election, so I'll leave it at that. I'm also closing comments on this post because I'm 99.999% sure you don't have anything interesting to say either (added a third 9 after the decimal point upon further consideration!).
razib | October 30, 2008Evolution of trust and trustworthiness: social awareness favours personality differences (Open Access):
Interest in the evolution and maintenance of personality is burgeoning. Individuals of diverse animal species differ in their aggressiveness, fearfulness, sociability and activity. Strong trade-offs, mutation-selection balance, spatio-temporal fluctuations in selection, frequency dependence and good-genes mate choice are invoked to explain heritable personality variation, yet for continuous behavioural traits, it remains unclear which selective force is likely to maintain distinct…
razib | October 29, 2008In response to a Conor Friedersdorf post on hard-working high earners I decided to look around for some data on the differences between socioeconomic categories in terms of hours worked weekly. In the GSS I found a modest association between higher income and more hours, but the N's were rather modest as well. Looking through google scholar I stumbled onto a different issue. Below the fold is a table from The Overworked American or the Overestimated Work Week?
Many years ago I did some QA data analysis for an engineering firm. More specifically it was a company which designed truck…
razib | October 29, 2008Princeon University Press now has a weblog. It looks like a good idea in terms of getting publicity for authors of academic books (and ideally, you get some value-add in terms of insight and experience). I wonder if Andrew Gelman's editor has tried to figure out how many extra copies of d State, Blue State, Rich State, Poor State were pushed because of he blogospheric publicity? Of course his sort of publicity will start to be less powerful once most academics start to publicize their work ahead of publication via web communication channels.
razib | October 28, 2008Dienekes has a interesting, if not surprising, post on how names can mold how we perceive people. I've posted on this before. The most extreme illustration of this tendency I've ever read is the fact that during segregation some southern hotels allowed international travelers from African countries with obvious black ancestry to check-in. I believe it is important to study and properly define the nature of the social construction of ethnic and racial identity, because it is just as important as the biological reality of race and ethnicity.
Of these two members of congress, one is a member…
razib | October 28, 2008There has been a lot of talk of Barack Obama "expanding the map" this cycle for the Democrats. In mid-September when John McCain was at his polling-peak many were assuming that had just been a pipe-dream, and that the traditional Democratic strategy of winning big blue states was back in play. But with the Obama bounce not so fast! So where is Obama exactly expanding he map? Below is a map generated by Andrew Gelman comparing Kerry's 2004 election results with current averaged poll numbers.
More charts an maps over at Red State, Blue State.
razib | October 26, 2008There was a comment below on Indian American ethnicity in terms of proportion. By "ethnicity," I mean the dominant language-based groups which serve as the organizing unit of many Indian states. The usual figures I see quoted are that 50% of Indian Americans are Gujarati, 25% Punjabi, with the balance a host of other groups (e.g., Bengalis, Tamils, Assamese, etc.). Digging around, I found these data:
In 2006, 26.3 percent of Indian immigrants age 5 and older reported speaking Hindi at home. Gujarathi (14.1 percent) was the next most popular language, followed by English (10.1 percent),…
razib | October 26, 2008William Saletan has an article out on the tendency for many Americans today to always be "hooked in" to technology through mobile devices (cell phones, iPods, etc.). I recall a woman loudly talking about her boyfriend leaving her, and the consequent emotional devastation, in front of me in the supermarket checkout line once. Only after 5 minutes did I notice the very subtle ear piece she was wearing (this was not the express line, so yes, 5 minutes). This was 3-4 years ago. Today my first hypothesis would likely be that she had an ear piece, not that she was schizophrenic, which is what I…
razib | October 24, 2008Linux Is Making Me Insane: Grappling with Ubuntu, the free, open-source operating system. I have Ubuntu on my PC through a dual-boot. I also purchased a USB wireless card which was guaranteed to be compatible with Ubuntu plug-and-play. It does work...80% of the time. The problem is that it "drops" the connection every half hour or so and I might have to end up rebooting the system to get it to work again. No thanks. There are some programs which only run on Linux systems that I keep Ubuntu around for (VMware is way too slow), but for browsing the internet it is just not useful for me.…
razib | October 24, 2008Obviously the most prominent Indian American politician today is Bobby Jindal, the governor of Louisiana. But Jindal is not very representative of Indian Americans:
...Additionally, there are also industry-wide Indian American groupings including the Asian American Hotel Owners Association and the Association of American Physicians of Indian Origin. Despite being heavily religious and having the highest average household income among all ancestry groups in the United States, Indian Americans tend to be more liberal and tend to vote overwhelmingly for Democrats. Polls before the 2004 U.S.…
razib | October 24, 2008Dienekes points to another paper on European population substructure, Genome-Wide Analysis of Single Nucleotide Polymorphisms Uncovers Population Structure in Northern Europe:
In this study, we analysed almost 250,000 SNPs from a total of 945 samples from Eastern and Western Finland, Sweden, Northern Germany and Great Britain complemented with HapMap data. Small but statistically significant differences were observed between the European populations...The latter indicated the existence of a relatively strong autosomal substructure within the country, similar to that observed earlier with…
razib | October 23, 2008John Wilkins points me to a piece by Pascal Boyer,* Being human: Religion: Bound to believe?:
So is religion an adaptation or a by-product of our evolution? Perhaps one day we will find compelling evidence that a capacity for religious thoughts, rather than 'religion' in the modern form of socio-political institutions, contributed to fitness in ancestral times. For the time being, the data support a more modest conclusion: religious thoughts seem to be an emergent property of our standard cognitive capacities.
If there is one thing you can say for philosophy, the discipline imposes a clarity…
razib | October 23, 2008David's penultimate post on Sewall Wright, Notes on Sewall Wright: The Shifting Balance Theory - Part 1:
Two catch-phrases indissolubly linked with Sewall Wright are the adaptive landscape, and the shifting balance. In preparing my note on Wright's concept of the adaptive landscape I was surprised to discover that Wright himself seldom if ever used this expression. I could not find a single example. I was therefore half-expecting that I would not find any reference to the shifting balance either - and I would have been half-right. Wright did use that term, but not, as far as I can find, until…
razib | October 23, 2008As you can see to the left Gene Expression hasn't raised that much money this year. That's not so hot, but, some of the other ScienceBloggers have raised a bunch, so that's heartening. I also wanted to add that Seed will be "padding" our contributions this year, but right now the amount that Seed is giving is multiples greater than what I've raised so far, so I hope readers can help me out a bit....