关键词: 服务计算, 信任度, 聚类, 评价, 信任演化

Abstract: The limitations of traditional service credible evaluation is studied in this paper.A novel method is proposed for service credible evaluation based on classification.To solve the three major problems for trust evaluation in service-oriented computing internet：data sparseness，cold start and scalability study.The novel credible evaluation method is proposed based on user and service characteristics of the similarity of classification and the trust is calculated by using the distance between the classes.The method of trust derivation is adopted by combing of traditional trust derivation and trust derivation based on classification.The novel method is proposed completely in this paper.Through theoretical analysis and experimental results show that：The new trust evaluation services can alleviate the user computing environment to a large extent，which including the data sparseness problem，new user participation and the existence of barriers of trust reasoning and evolution of trust exist rationality and scalability issues.Experimental results show that the method significantly improves the system’s trust evaluation accuracy.

Key words: Web services computing, trust level, clustering, evaluation, trust evolution