POLITICAL CLIQUES….Yesterday I wrote a couple of posts about alternate views of the war, one from Saudi Arabia and one from Robert Fisk, and this led to an email exchange with Nicholas Pisarro over at Dark Machine about “confirmation bias,” the tendency of people to pay attention to evidence that supports their views and to dismiss evidence that contradicts it ? even if the credibility of both pieces of evidence is about the same.

By chance, I came across an interesting and related item while reading Discover last night. Valdis Krebs is the author of a piece of software that analyzes social networks, and on a whim he decided to use it to find out if buying patterns at Amazon.com could be used to draw conclusions about the polarization of American politics:

“I started thinking, I wonder if you could see evidence for this in the book-reading networks.” Krebs used InFlow to analyze the network of book purchases surrounding two best-selling titles, one from the left (Michael Moore’s Stupid White Men) and one from the right (Ann Coulter’s Slander).

“What I got were two cliques that were about as distinct as they could be. I kept looking for paths that crossed between them. Every time I tried to follow one of these paths, I’d go out three or four steps, and then boom, I’m right back in the clique.” Most strikingly, the two networks intersected only on a single title: Bernard Lewis’s What Went Wrong? Otherwise, the two groups were engrossed in entirely different reading lists, with no common ground.

Granted, these are pretty extreme books and appeal to pretty extreme audiences, but it’s still an interesting little data point about the discomfort people have even listening to arguments they disagree with.

And while we’re on the subject, Nicholas recommends this Christian Science Monitor article about war reporting and confirmation bias. Check it out.