Measurement Error and the Relationship between Investment andq
发现，投资与现金流之间的显著关系很大程度上源于对边际q的测量误差；在纠正测量误差后，现金流不再重要，q理论具有良好的解释力。
Many recent empirical investment studies have found that the investment of financially constrained firms responds strongly to cash flow. Paralleling these findings is the disappointing performance of the q theory of investment: even though marginal q should summarize the effects of all factors relevant to the investment decision, cash flow still matters. We examine whether this failure is due to error in measuring marginal q. Using measurement errorconsistent generalized method of moments estimators, we find that most of the stylized facts produced by investment-q cash flow regressions are artifacts of measurement error. Cash flow does not matter, even for financially constrained firms, and despite its simple structure, q theory has good explanatory power once purged of measurement error.