I got a gratifying response to my trust metric rant in the last post - a couple of emails, some blog comments. It's clear now that I need to do a more detailed writeup of exactly how to implement the eigenvector-based trust metric in the context of a large Wiki.
Pete Zaitcev writes: One half is spam and abuse, and other half is that conventional, highly credible and trusted wisdom is simply wrong. I'm not sure exactly what he means by this, but it may have something to do with the fact that, from the perspective of approximately one half of the population of this country, approximately the other half is under the spell of a mass psychosis in which the usual rules of reality simply don't apply anymore.
It's not clear to me how a large wiki should handle this situation. One intriguing possibility is that the subgraphs of sane people and deluded people both form cliques, so that when a sane or deluded person is logged in and the trust metric is computed from their node, they see a version of the page that is factual and objective, or conforms to the parameters of their delusion, respectively.
The Clever search engine from IBM research has an interesting take on this issue. While PageRank and the Advogato trust metrics compute the principal eigenvector, they also compute some of the others, resulting in "clusters". They report, for example, that the second eigenvector link graph for webpages on abortion neatly separates pro-life from pro-choice. Indeed, this very eigenvector is likely to correlate very strongly with the sane/deluded distinction described above. The sign of this correlation is, of course, left as an exercise for the reader.
My teeth are a bit sore. Turned out the cavity I was to have filled today had more decay than expected, so I get to have a crown instead of a filling. Could have been worse, it didn't go into the nerve, so I don't need a root canal.