Research Of The Users’ Explicit And Implicit Elationship Of Online Social Network

Because the need of information acquisition, communication and personal expressionincreases, a new type of social network, that is online social network, has emerged anddeveloped quickly. Rapid development of online social networks makes user behavior,relationship, structure and evolution of network as new hot topic of research.The traditional research analyses the feature of structure and evolutional law of socialnetworks from the existing user relationship networks. Based on two online socialnetworks, social tagging system and weibo system, this paper study the user behavior andcommunication feature, propose two user relationships: explicit relationship and implicitrelationship. The explicit relationship is the tie of users of adding friends or followingmutually. From the users’ behavior, we can study the users’ interest and preference, andthen construct users’ profile. Based on users’ profile, we can calculate the similaritybetween users. If the similarity exceeds some given threshold, we can consider there existssome implicit relationship between users. From an experimental viewpoint this paperstudies the feature of structure of explicit and implicit user social network of delicious andsina weibo. The explicit and implicit social network of both systems have the highclustering coefficient and low average shortest path, so both exhibit small world property.And this experimental result means user can communicate with each other through shortpath, and users’ relationship networks are sparse. The explicit user relationship networkmeets power-law degree distribution. While the degree of correlation coefficient isnegative, indicating the user having high degree prefer to communicate with the userhaving low degree. And users of sina wibo are more obvious than those of delicious in thisproperty.The proposed explicit and implicit social network have same common feature, butalso have different feature. This is the basis of further recommendation of users andresources, and is also very important to the transform from the implicit network to explicitnetwork and the evolution of explicit social networks. And it is also useful to understandthe structure, development, evolutional regularity of online social netwok.