Price versus quantity measures to deal with pollution and congestion in urban areas: A political economy approach
通过政治经济学模型解释了为何城市更常采用基于车龄的数量限制而非价格机制来治理污染和拥堵，并阐明了混合系统、试行期、公交投资及高收入城市集中实施数量限制等典型事实。
Pollution and congestion in urban areas are serious externalities that can be mitigated through the adoption of either price- or quantity-based mechanisms. While price restrictions are occasionally applied, quantity constraints based on car vintage are becoming increasingly popular. Our model provides a comprehensive analysis that explains this prevalence of quantity over price schemes. We also elucidate some other stylized facts observed in urban areas applying traffic restrictions, such as the implementation of hybrid price-and-quantity systems, the use of trial periods, the commitment to invest in public transit to enhance the acceptability of urban tolls, and the concentration of quantity restrictions in high-income cities.