Timing Decisions and the Behavior of Mutual Fund Systematic Risk
分析专业管理组合（尤其是共同基金）的投资绩效，将绩效分解为选股能力和市场时机把握能力，帮助理解基金经理的决策来源。
The investment performance of professionally managed portfolios, in general, and mutual funds, in particular, has been the subject of considerable attention in finance. Fama [9] has suggested that overall portfolio performance be broken down in such a manner that the individual sources of performance can be identified. Two basic sources are: (1) the ability of the portfolio manager to forecast price movements of individual common stocks relative to stocks in general (selectivity or microforecasting); and (2) the ability to forecast the direction of the stock market relative to fixed income securities (timing or macroforecasting).