Today's post, The Error of Crowds was originally published on April 1, 2007. A summary (from the LW wiki):
Mean squared error drops when we average our predictions, but only because it uses a convex loss function. If you faced a concave loss function, you wouldn't isolate yourself from others, which casts doubt on the relevance of Jensen's inequality for rational communication. The process of sharing thoughts and arguing differences is not like taking averages.
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The post seems to imply that you should put your fingers in your ears; but wouldn't it be better to randomly choose between the single highest and single lowest first-round answers?
The article contains a link to an image at http://www.zoo.ufl.edu/bolker/emd-2000/jensen2.gif, which is now bad. Does anyone have a similar image to replace it?
This image was posted here.
In potentially relevant research news: "How social influence can undermine the wisdom of crowd effect". (I haven't read the paper yet, only skimmed it.)