Pioneering and Market Share: Is Entry Time Endogenous and does it Matter?
指出以往研究将先发优势视为外生变量存在偏误，通过理论模型和豪斯曼检验证实进入时间的内生性，并发现内生估计与有偏的外生估计在统计和实际显著性上存在实质差异。
All previous empirical work assessing the effects of pioneering on firm performance treats pioneering as an exogenous variable. The authors develop a theoretical model of the entry decision that suggests treatment of pioneering as an endogenous variable. They test the model by reestimating a recent empirical pioneering model. Using Hausman's specification test, they find statistically significant bias in the exogenous pioneering model. In assessing the effect of pioneering on market share, they find substantive differences between the biased and inconsistent exogenous pioneering estimates and the consistent endogenous estimates in terms of both statistical and practical significance.