The reason to take this projection seriously is Eisenstadt’s track record. Consider a statistic known as the r-squared, which measures the degree to which one data series predicts or explains another. If the first series perfectly predicted the second, the r-squared would be 1.0; if the first series had absolutely no predictive ability the r-squared would be zero.
For the data plotted in the chart below, the r-squared is 0.31, which is significant at the 95% confidence level that statisticians often use when determining if a pattern is genuine. Though you might be disappointed that this r-squared isn’t higher, you should know that most of the models that get attention on Wall Street and in the financial press have r-squareds that are far lower—if they’re not actually zero.
Eisenstadt constructs his model to include all factors he has found to have an ability to project the stock market’s subsequent six-month return. Though his model is proprietary, Eisenstadt has told me that two of the more important inputs are low interest-rates and market momentum. Both factors are mildly positive right now.No forecast is complete without some understanding of the risks to the forecast. When I peek under the hood of the Eisenstadt's model, interest rates and momentum represent sources of both risk and opportunity to the market. Investors will have to judge for themselves whether a potential 6-month gain of 3% is worth the risk.