Willingness to Pay for Clean Air: Evidence from Air Purifier Markets in China
利用中国空气净化器销售数据，估计家庭为清洁空气的支付意愿，发现家庭每年愿支付1.34美元去除1微克/立方米的PM10，并评估了环境政策与近年空气质量改善的价值。
We develop a framework to estimate willingness to pay for clean air from defensive investments on differentiated products. Applying this framework to scanner data on air purifier sales in China, we find that a household is willing to pay $1.34 annually to remove 1 μg/m3 of air pollution (PM10) and $32.7 annually to eliminate the pollution induced by the Huai River heating policy. Substantial heterogeneity is explained by income and exposure to information on air pollution. Using these estimates, we evaluate various environmental policies and quantify the value of recent air quality improvements since China declared a war on pollution in 2014.