The Changing Impact of Analyst Recommendation Revisions over Time: an Analysis of the German Stock Market

The Efficient Markets Hypothesis beholds that all public information is incorporated in the stock price. Yet economists question to what extent this holds, and these discussions are, among other factors, fuelled by the existence of analyst recommendations. If all information is already incorporated in the stock price, what value can analysts add? A comprehensive study on the German market finds that, indeed, a tangible effect is measured after analysts voice their recommendations; this effect is especially powerful when an analyst changes his recommendation to his previous one. Moreover, this book is the first to research how analyst recommendations have changed over time, whether analysts have better forecasting power during bull or bear markets, and, most importantly, how can an investor profit from this knowledge? An advanced calendar-time strategy has been developed wherein an investor can earn significant abnormal returns by following a momentum strategy in the short-term while simultaneously abiding to a contrarian strategy in the long-term.