中文摘要：

在已有的中心性分析工作的基础上，采用聚类分析对中心性结果进行深入挖掘，得到不同等级的国家集合。结果表明，欧盟国家和美国作为国际贸易的“一类国家”，具有举足轻重的地位。近年来发展中国家如中国和印度在国际贸易中的作用和影响力也不容忽视。该结果通过横向比较更加直观的展现世界贸易格局，为政策制定者提供更真实的参考依据。

英文摘要：

Centrality analysis is an important in the study of international trading network.Cluster analysis is used here to explore centrality results and to obtain different collections of countries.Data indicated that EU and USA play a crucial role in world trade.But developing countries such as China and India cannot be ignored in recent years.The intuitive data presented here allow us to better understand world trade patterns and to facilitate horizontal comparison for scholars,and to provides more realistic reference basis for policy makers.