Ruminations on Investment Performance Measurement
这篇演讲对投资绩效测量现状提出五点看法：传统阿尔法不可信，随机贴现因子阿尔法更优；夏普比率合理使用可作绩效指标；持仓法有缺陷并给出改进建议。
Abstract This is a summary of a keynote address to the European Financial Management Symposium on Asset Management in April 2012. It makes five observations about the state of the art in investment performance measurement. First, the traditional alphas used in performance measurement are not to be trusted as normative indicators for when to buy or sell funds, but Stochastic Discount Factor (SDF) alphas are better. Traditional alphas can be equivalent to the correct SDF alphas, but this requires that an Appropriate Benchmark be used. Third, mean variance efficient portfolios are almost never Appropriate Benchmarks. Fourth, Sharpe ratios can be justified as performance measures, if they are properly used. Finally, current holdings‐based approaches to performance measurement are also flawed, but I offer some suggestions for improving them.