Anticipation, Tax Avoidance, and the Price Elasticity of Gasoline Demand
研究发现，汽油税作为价格工具存在内生性，因为消费者会在加税前增加购买、减税前推迟购买，导致传统工具变量法高估弹性；加入合适的领先和滞后项后，估计出的弹性值大幅降低。
Summary Least‐squares estimates of the response of gasoline consumption to a change in the gasoline price are biased toward zero, given the endogeneity of gasoline prices. A seemingly natural solution to this problem is to instrument for gasoline prices using gasoline taxes, but this approach tends to yield implausibly large price elasticities. We demonstrate that anticipatory behavior provides an important explanation for this result. Gasoline buyers increase purchases before tax increases and delay purchases before tax decreases, rendering the tax instrument endogenous. Including suitable leads and lags in the regression restores the validity of the IV estimator, resulting in much lower elasticity estimates. Copyright © 2016 John Wiley & Sons, Ltd.