Market Penetration Costs and the New Consumers Margin in International Trade
构建了一个包含营销成本的贸易模型，解释了企业进入市场与市场规模的正向关系，以及众多小型出口商共存的现象，并预测贸易自由化会大幅增加此前贸易量低但为正的商品贸易。
This paper develops a novel theory of marketing costs within a trade model with product differentiation and heterogeneity in firm productivities. A firm enters a market if it is profitable to incur the marginal cost to reach a single consumer. It then faces an increasing marginal penetration cost to access additional consumers. The model, therefore, can reconcile the observed positive relationship between entry and market size with the existence of many small exporters in each exporting market. Comparative statics of trade liberalization predict a large increase in trade for goods with positive but low volumes of previous trade.