Will an avian-flu epidemic lay waste to millions? Will terrorists strike the New York City subway system before Christmas? Where will the next hurricane make landfall? None of us knows the answers to those questions. But we just might have a better idea than the experts, and our predictions on such matters could prove useful in helping us plan our lives, our portfolios or our escape routes.
The power of markets, it turns out, has something to say about practically everything. We see it at work on Wall Street, which absorbs the collected wisdom of millions of investors and expresses it...