I had to think about this one for a long time, but I decided that this is a category that I should not vote in.
I kept trying to figure out how to judge editing. There aren't really metrics around good editing that I can see other than "the story was good". But is the story good because the author did an amazing job that didn't require much editing, or because the editor saw the potential in a story and did an amazing job whipping that story into shape? Unless you saw the story before it was edited, there isn't a way for the reader to really know.
Since I do not want to vote for an editor without really knowing anything about their ability, I'm choosing to bow out of voting in those particular categories.