Price and return models
比较了价格模型（股价对每股收益回归）和回报模型（回报率对盈余变量回归）的优劣，发现价格模型估计系数更无偏，但回报模型计量问题更少，建议根据研究情境选择或结合使用。
Return models (returns regressed on scaled earnings variables) are commonly preferred to price models (stock price regressed on earnings per share). We provide a framework for choosing between these models. An economically intuitive rationale suggests that price models are better specified in that the estimated slope coefficients from price models, but not return models, are unbiased. Our empirical results confirm that price models' earnings response coefficients are less biased. However, return models have less serious econometric problems than price models. In some research contexts the combined use of both price and return models may be useful.