中文摘要
本文提供了一个全面的框架，用于研究不完全竞争下多种政策干预及其他外部变化的福利效应，并以从量税和从价税作为主要案例加以强调。具体而言，在税收转嫁方面，我们在相当一般的需求、生产成本和市场竞争类别下，为两个福利度量提供了“充分统计量”公式。这两个度量是： 公共资金的边际价值（即消费者剩余和生产者剩余相对于政府净成本增加的边际变化），以及 归宿（即消费者剩余的边际变化与生产者剩余的边际变化之比）。我们首先从同时面临从量税和从价税的对称企业情形出发，推导出一组简单且具有实证相关性的公式。随后，我们利用税收收入的思想——将其设定为一个由政策工具向量参数化的一般函数，这些政策工具包括政府和非政府干预以及税收之外的成本——将这些结果大幅推广至涵盖企业异质性的情形。
Abstract
This paper provides a comprehensive framework to study welfare effects of multiple policy interventions and other external changes under imperfect competition with emphasis on specific and ad valorem taxation as a leading case. Specifically, in relation to tax pass-through, we provide “sufficient statistics” formulas for two welfare measures under a fairly general class of demand, production cost, and market competition. The measures are (i) marginal value of public funds (i.e., the marginal change in consumer and producer surplus relative to an increase in the net cost to the government), and (ii) incidence (i.e., the ratio of a marginal change in consumer surplus to a marginal change in producer surplus). We begin with the case of symmetric firms facing both unit and ad valorem taxes to derive a simple and empirically relevant set of formulas. Then, we provide a substantial generalization of these results to encompass firm heterogeneity by using the idea of tax revenue that is specified as a general function parameterized by a vector of policy instruments including government and non-government interventions and costs other than taxation.