Abstract
This study proposes a new system, analyzing a relationship among Internet Auction users. As a relationship among the users organizes a complex network, the system treats users and dealing relations between users as a set of vertices and a set of edges. Also, the system employs the network-analyzing tool, "Pajek". The proposed system analyzed the real dealing records extracted from "Yahoo! Auctions". As a result, the clustering coefficient explains that a collector user's degree has a strong relation with making a group formation and the closeness centrality explains that some pattern reveals in choosing partners for dealing.
