中文摘要：

基础设施水平的提高可以促进市场融合,使企业拓宽市场边界,实现企业和国家的市场规模扩张,有利于大国经济效应的发挥.基础设施之所以能够扩大企业的市场边界,原因在于基础设施降低了运输成本,使得整体市场规模比原先没有基础设施时的市场规模更大,这为大国经济的进一步发展创造了重要条件.

英文摘要：

The improvement of infrastructure facilitates market integration, enables firms to enlarge their market sizes, contributes to the market expansion of firms and countries, and thus is beneficial to the realization of large country effect. The reason why infrastructure can enlarge the market size is that infrastructure helps reduce transportation cost, resulting in larger market scale in economies compared with the case with no infrastructure and contributing to further development of large economies.