Abstract:

Concerning the present situation that Quality of Service (QoS) evaluation methods ignore the implicit service quality assessment and lead to inaccurate results, a service evaluation method that comprehensively considered explicit and implicit quality attributes was put forward. Explicit quality attributes were expressed in vector form, using service quality assessment model, after quantization, normalization, then evaluation values were calculated; and implicit quality attributes were expressed according to the evaluation on similar users' recommendation. The users' credibility and difference between old and new users were considered in the evaluation process. Finally the explicit and implicit quality evaluation was regarded as the QoS evaluation results. The experiments were performed in comparison with three algorithms by using one million Web Service QoS data. The simulation results show that the proposed method has certain feasibility and accuracy.

Key words: explicit Quality of Service (QoS), implicit QoS, trusted, assessment, service selection

摘要：

针对目前服务质量(QoS)评估方法中忽视对服务隐式质量的评估而导致结果不准确的问题，提出了一种综合考虑显式和隐式质量属性的服务评价方法。首先，显式质量属性以向量形式表达，采用服务质量评估模型，经过量化、归一化，计算出评估值；然后，隐式质量属性以用户评价间接表达，根据评价相似用户的推荐而完成对隐式服务质量的评价，评估过程考虑推荐用户的可信性和新老用户的区别；最后综合显式和隐式质量评价作为服务质量评价结果。使用100万条Web服务的QoS数据与其他3类算法进行了对比实验。仿真实验证明了所提方法的可行性与准确性。

关键词: 显式服务质量, 隐式服务质量, 可信性, 评估, 服务选择