Abstract
Using Swedish stock market data, this study investigates whether an investment strategy based on publicly available accounting information can generate abnormal investment returns. The strategy involves two steps. First, an accounting-based probabilistic prediction model of changes in the medium-term book return on owners' equity (ROE) is estimated. Second, market expectations of changes in medium-term ROE are assessed through observed stock prices and the residual income valuation model. Stock market positions over 36-month holding periods are taken when the accounting-based predictions of ROE and the market expectations differ. Over the period 1983-2003, the investment strategy generated values of Jensen's alpha corresponding to an average monthly excess return for a hedge position of up to 0.8% for a sample of manufacturing companies. In the main this hedge return was caused by strong positive returns to the long positions, and additional analyses show that the returns appear to have been affected by a positive market sentiment bias (i.e., positive ROE surprises being associated with stronger price reactions than negative ROE surprises) making out-of-sample inferences somewhat dubious. Furthermore, most of the investment returns accrued over holding periods up to around 1995, with no indications of market mispricing over the last third (1995-2003) of the investment period. The empirical results are consistent with market investors having become more sophisticated in their use of publicly available accounting information over time.