From Hulbert, who monitors investment news letters.
I plugged into my PC's statistical software the trading history back to January (all that were available) for the InTrade futures contract that was tied to the passage of health-care reform. I also plugged in daily changes of the Wilshire 5000 index (representing the combined value of all publicly traded stocks in the U.S.) and of the Health Care Select Sector SPDR (XLV 32.46, +0.21, +0.65%) (representing the health-care sector).
I could find no statistically significant correlations, either with the overall market or with the health-care sector in particular. In fact, even though it was not statistically significant, the stock market more often rose along side the InTrade contract than fell. That is just the opposite of what you would have guessed by reading the commentary of the advisers I monitor.
Investors should draw several lessons from all of this. Perhaps the most important is to subject to empirical testing the assertions and beliefs on which we might otherwise base our investment decisions. This is especially crucial when it comes to matters that are ideologically charged, such as health-care reform, since it is easy in such cases for us to let our strongly-held beliefs be the substitute for objective, rigorous testing.