Price Discrimination in Free-Entry Markets
用空间垄断竞争模型研究自由进入、零利润市场中的价格歧视，发现品牌异质时竞争不阻止歧视，且按品牌偏好强度分类比按保留价格分类产生更大价差但福利效果更差。
Using a spatial model of monopolistic competition, we investigate price discrimination in free-entry, zero-profit markets. We show that when brands are heterogeneous, competition does not prevent discrimination. The power to earn economic profits is not necessary for a firm to maintain discriminatory prices. Our model treats formally the fact that consumers difer not only in the utility they derive from a good, but also in how strongly they prefer one brand over all others. In markets where firms are very competitive, sorting consumers on the strength on brand preference produces larger price differentials between groups than sorting on the basis of consumers' reservation prices for the good. When firms sort customers on the basis of strength of brand preference, however, we find that the output and welfare effects are generally less favorable than when sorting is more closely related to consumers' reservation prices.