Income Elasticity of Willingness to Pay for Better Air Quality: Effect of a Private Environmental Substitute
研究了私人环境替代品如何影响人们对改善空气质量的支付意愿的收入弹性，发现替代品价格越高、收入越低，支付意愿的收入弹性越大，且替代品购买减少会降低社会平均支付意愿。
We use a nested constant elasticity of substitution utility function to introduce a private environmental substitute in a theoretical model. We find that a buyer’s income elasticity of willingness to pay (WTP) increases with the price of the substitute and decreases with income. A higher price and a lower income also discourage purchase of the substitute, reducing the proportion of buyers in population. We must therefore consider both dimensions when discussing societal mean WTP. An empirical check based on a contingent valuation survey confirms our theoretical findings. Projected income-WTP curves reveal inequality further reduces the mean WTP in the presence of private environmental substitutes.