Recently we have opened an experimental website for Rational Discussion of Politics. A special feature of the new website is an automated recommendation system which studies user preferences based on their voting records. The purpose of this feature is to enhance the quality of discussion without using any form of censorship.
The recommendation system was previously tested with the help of 30 members of a political discussion forum. The tests have shown that most user preferences can be reasonably well described by just two parameters. The system chooses the parameters (principal vectors) independently based only on the numerical data (comment ratings), but it was easy to see that one vector corresponded to the “leftwing - rightwing” and another to the “well written – poorly written” axis.
About a month ago we started discussions on the new website. This time, all our participants were LW members and the results were very different. There was relatively little variation along “well written – poorly written” axis. There was significant variation along what seemed to be the political views axis, but it could no longer be perfectly described by the conventional “leftwing - rightwing” labels. For the moment, we adopted “populares” and “optimates” terms for the two camps (the former seems somewhat correlated with “left-wing/liberal” and the latter with “right-wing/libertarian”).
The results have shown an interesting asymmetry between the camps. In the previous tests, both left and right leaning users upvoted users from their own camp much more frequently. However, one group was several times more likely to upvote their opponents than the other. Among “populares” and “optimates” the asymmetry was a lot weaker (currently 27%), but still noticeable.
In both cases our sample sizes were small and may not be representative of the LW community or the US population. Still, it would be interesting to find an explanation for this asymmetry. One possibility is that, on average, one side presents significantly better arguments. Another possibility is that the other group is more open-minded.
Can anyone suggest a test that can objectively decide which (if any) hypothesis is correct?