http://tinyurl.com/yr3n5h

Having said that, there simply has to be a better model to incentivize productive participation in comment threads and encourage moderation behaviors in a way that avoids the “tragedy of the commons” scenario you describe (love the term, btw).

Digg’s “display more low rated comments by default” mindset ties in well with the fact that any user can moderate at any time. The underlying assumption is that moderation will happen quickly and often. It takes five negative moderations to hide something because the system assumes that both the good and the bad will draw users’ attention pretty much immediately.

The gotcha in this theory may be the very fact that people can moderate at any time…a sort of bizarre take on the tragedy of the commons: people don’t moderate much because “eh, somebody else will do it.”

As a normal Slashdot user you don’t have the opportunity to moderate every day, and are given very limited power to moderate when the opportunity is granted (last time I recall moderating I had five mod points to work with).

I have only myself to present as data, but I certainly do tend to moderate on Slashdot in as thoughtful a manner as possible when the opportunity comes up, simply because it doesn’t come up all that often. It’s a minor and occasional imposition on my time, so it seems worth doing well. In addition, Slashdot has a meta-moderation system in place, where users check the moderation that was done by others and not whether they agree or disagree with the mod; while this certainly doesn’t elimiate abusive moderation, it’s a useful check to have in place.

I expect that over time Digg’s moderation tools will evolve…not in exactly the same direction as Slashdot, of course, but very likely in the direction of creating a more user-managed approach to community.