Financial Planner Carl Richards, warns investors about relying too much on market predictions. He cites the law of small samples as one way things go wrong. Another is investment managers with good track records in one decade doing badly in the next decade- David Miller in the 70's and Bill Miller of the Legg Mason Value Fund are others. To show how ridiculous market predictions based on computer models can get he gives the example of a researcher who found that over a 13 year period butter production in Bangladesh 'explained' 75% of the fluctuations in the annual returns of the Standard & Poor's 500 stock index. Adding in U.S. cheese production and the total population of sheep in Bangladesh and the U.S., this researcher was able to forecast past U.S. stock returns with 99% accuracy.