Does Sutton apply to supermarkets?
利用萨顿（1991）框架，构建超市竞争模型，证明内生固定成本（如配送系统投资）决定了市场均衡结构，并基于51个地理市场的门店级数据，发现超市行业是天然寡头市场，无论市场规模大小，少数企业（4-6家）占据大部分销售额。
I present empirical evidence that endogenous fixed costs play a central role in determining the equilibrium structure of the supermarket industry. Using the framework developed in Sutton (1991), I construct a model of supermarket competition where escalating investment infirm‐level distribution systems is driven by the incentive to produce a greater variety of products in every store. Employing a store‐level census and 51 distinct geographic markets, I demonstrate that the supermarket industry is a natural oligopoly in which a small number of firms (between four and six)capture the majority of sales, regardless of market size.