The welfare effects of third‐degree price discrimination with nonlinear demand functions
分析当两个市场的需求互为平移且统一定价时，三级价格歧视对社会福利的影响。若需求斜率对数凹或需求凸性随价格非递减，则歧视降低福利。常用不完全竞争模型的需求函数满足这些条件。
The welfare effects of third‐degree price discrimination are analyzed when demand in one market is an additively shifted version of demand in the other market and both markets are served with uniform pricing. Social welfare is lower with discrimination if the slope of demand is log concave or the convexity of demand is nondecreasing in the price. The demand functions commonly used in models of imperfect competition satisfy at least one of these sufficient conditions.