Skewness Preference and the Popularity of Technical Analysis

The popularity of technical analysis is puzzling. We propose a simple model of how investors evaluate a trading rule, and show that the market timing of technical trading rules induces lottery-like trading profits. Therefore, investors' preference for positive skewness caters to the popularity of technical analysis. Since prospect theory implies strong skewness preference, it can explain why investors trade extensively on chart patterns that are meaningless in light of the efficient market hypothesis. Advocates of technical analysis often invoke behavioral finance as its theoretical foundation. Contrary to this view, our paper shows that ideas from behavioral finance can explain why technical analysis is popular despite its lack of theoretical foundation and empirical success