How does this affect those posting as visitors or under generic names?
While karma based systems work well for some sites, I think there is a readership threshold below which its effectiveness degrades significantly. Too many people rate based on whether or not they agree with a comment, and not the quality of the comment. While this can be a problem on sites like Slashdot too, usually they have enough people that seem to fix that except when for very minority opinions. As opposed to here, where it seems many comments get rated by one person, often some nasty patterns (or potential patterns, hard to do much more than guess original intentions), like low rating for the other person in a two person argument that might just be from the other person, or some people getting "stalked" by negative reviewers regardless of what they post. I suppose the former example is eliminated by Slashdot's style of blocking ratings from people who have posted in a particular comment, but that would further limit the number of ratings.
How does this affect those posting as visitors or under generic names?
While karma based systems work well for some sites, I think there is a readership threshold below which its effectiveness degrades significantly. Too many people rate based on whether or not they agree with a comment, and not the quality of the comment. While this can be a problem on sites like Slashdot too, usually they have enough people that seem to fix that except when for very minority opinions. As opposed to here, where it seems many comments get rated by one person, often some nasty patterns (or potential patterns, hard to do much more than guess original intentions), like low rating for the other person in a two person argument that might just be from the other person, or some people getting "stalked" by negative reviewers regardless of what they post. I suppose the former example is eliminated by Slashdot's style of blocking ratings from people who have posted in a particular comment, but that would further limit the number of ratings.