I don't think I get many down votes at all.  Out of interest I started tracking my karma a while ago to try to detect these sorts of changes and influences.  I seem to get very few down votes.<p>The pattern seems to be more that I make a few contributions that are seen and well regarded.  They get lots of votes.  I make a few contributions that don't get noticed, or that no one likes.  They get no votes.  And I make a lot of contributions that cross-reference, location duplications, point people to other discussions, and generally try to help tie things up.  I do that because my background in online communities is more in wiki technology, where house-keeping is essential.<p>Those many, many contributions get very little attention, and no up votes.  The net result is that all the small notes that try to make things better drag my average down.<p>I think the use of the average karma is mis-guided.  At least I can see what mine is, as I'm on the leader board.