I think that a downside of the karma system is that it is likely to put off people who have good ideas but are nervous about sharing them from commenting. I think these people are disproportionately women.
However, the karma system works really really well and massively contributes to the high quality of discussion here. So I don't have a solution!
I did a quick google search and found that women are more risk adverse than men (at least in financial decisions - that's what most of the studies were about). If that generalizes to social situations, then women would have more fear of disapproval of their comments than men, independent of their intelligence. (I've talked to people who say they are scared to post because they think they're not as smart as other LessWrong users, but I don't know how common that is.)
I don't think it's just because of the karma system. People here also aren't shy about telli...
Today's post, Of Gender and Rationality was originally published on 16 April 2009. A summary (taken from the LW wiki):
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