报告题目：Large Firms in Retail Markets: Multiple Products for Heterogeneous Consumers
徐铭梽，北京大学新结构经济学研究院助理教授。2018年毕业于美国加州大学戴维斯分校（University of California Davis）获得经济学博士学位。于2018至2019年期间，担任美国国家经济研究局（the National Bureau of Economics Research, NBER）博士后研究员，并于同年在哈佛大学肯尼迪政府学院（Harvard University, Kennedy School of Government）担任访问研究员。研究方向包括国际经济学，产业组织结构以及经济发展相关议题。
We study the ability of firms of various sizes to cater to the taste of consumers who differ in their geographic location, store choice, and type or purchase history. Using data on purchases at the household-barcode level from Nielsen, we find that heterogeneity across consumer segments accounts for 39% of the variation in product appeal, which is a key determinant of firm size. Using a model with heterogeneous consumers, we find that consumer heterogeneity increases markups and profits, and such a positive effect is more pronounced for large firms. Furthermore, we find a link between firm size heterogeneity and the strategies firms follow in the presence of heterogeneous consumer segments. While smaller firms cater to the taste of few segments, typically the largest ones, larger firms exploit their wider scope to target a larger number of segments, both large and niche. Our quantitative model rationalizes the difference in strategies with the presence of segment-specific market costs.