Difference-in-Differences Hedonics
澄清了双重差分等准实验方法在特征价格模型中的福利含义，证明其可识别事后价格函数的移动，并作为一般均衡福利的下界，从而无需复杂结构模型即可恢复非边际福利，并以有毒设施与房价为例说明。
Cross-sectional estimates of hedonic price functions theoretically recover marginal values for characteristics but face endogeneity problems. Consequently, economists have introduced difference-in-differences and other quasi-experimental econometric methods into hedonic models. Unfortunately, the welfare interpretation of these estimands has not been clear. This paper shows that quasi-experimental hedonics can identify the movement along the ex post price function. It further shows that this effect is a lower bound on general equilibrium welfare. Thus, nonmarginal welfare can be recovered using transparent designs without Rosen’s second stage or more structural models. The paper illustrates these results with an application to toxic facilities and housing prices.