Comment: The Information Content of Daily Market Indicators

Louis Bachelier would be pleased with the findings reported in John T. Emery's paper, even though Bachelier wrote in 1900 before there was any popular support for technical analysis. Considering technical analysis historically, the Dow Theory was the first popular technical approach, although Charles H. Dow, editor of The Wall Street Journal at about the time of Bachelier's writing, did not consider his theory a forecasting method. Later William P. Hamilton began to forecast with Dow's Theory, and then in 1932 Robert Rhea's publication of The Dow Theory popularized this technical approach. Earlier Bachelier had struck the first blow of an obviously continuing quest to execute the technical security analysts. (A technical security analyst, often called a chartest, develops esoteric charts or computer printouts which he hopes will allow him to make better than average returns in the stock market.) In the United States serious economic and statistical testing of technical analysis did not begin until the early 1950s; these academic tests continue today. Test results support the efficient capital market theory or, put more bluntly, technical analysis does not lead to greater than average profits in the stock market. On the other hand, perhaps technical analysis does work, but no statistical method used in testing has uncovered this fact. In short, perhaps our statistical tools are not sophisticated enough to disclose the relation between stock price and “daily market indicators.â€