Markets are only hard-to-predict in terms of future prices and returns. If all you want to do is to compare the relative value of two assets, the current price

Markets are only hard-to-predict in terms of future prices and returns. If all you want to do is to compare the relative value of two assets, the current price is a great place to start out. For example, the market is pretty sure that Exxon Mobil is worth vastly more than Groupon. Likewise, a prediction market does just fine at telling you stuff like "Romney is much more likely than Ron Paul to be the Republican candidate."