Discovering admissible Web services with uncertain QoS
Discovering admissible Web services with uncertain QoS
复制标题
发现具有不确定 QoS 的可接受的 Web 服务
DOI：
10.1007/s11704-014-4059-9
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发表时间：
2015
影响因子：
4.2
通讯作者：
Feng Yong
中科院分区：
文献类型：
--
作者：
Fu Xiaodong;Yue Kun;Liu Li;Zou Ping;Feng Yong
开放和动态的环境导致Web服务QoS（Quality of Service）具有内在的不确定性，QoS感知的服务选择问题可以看作是一个不确定条件下的决策问题。我们使用经验分布函数来描述从历史交易中获得的分数的不确定性。然后，我们提出了一种方法来发现可接受的服务，包括替代服务，不占主导地位的任何其他替代品，根据预期的效用标准。随机优势（SD）规则被用来比较两个服务的不确定的分数，而不管其不确定的分数的分布形式。利用SD规则的性质，提出了一种减少SD测试次数的算法，使可接受的服务能够逐步上报。我们证明了该算法可以运行在分区或增量替代服务。此外，我们得到了一些有用的理论结论，正确修剪不必要的计算和比较，在每个SD测试，通过SD测试的效率可以提高。我们使用真实的数据集进行了全面的实验研究，以评估所提出的算法的有效性，效率和可扩展性。
Open and dynamic environments lead to inherent uncertainty of Web service QoS (Quality of Service), and the QoS-aware service selection problem can be looked upon as a decision problem under uncertainty. We use an empirical distribution function to describe the uncertainty of scores obtained from historical transactions. We then propose an approach to discovering the admissible set of services including alternative services that are not dominated by any other alternatives according to the expected utility criterion. Stochastic dominance (SD) rules are used to compare two services with uncertain scores regardless of the distribution form of their uncertain scores. By using the properties of SD rules, an algorithm is developed to reduce the number of SD tests, by which the admissible services can be reported progressively. We prove that the proposed algorithm can be run on partitioned or incremental alternative services. Moreover, we achieve some useful theoretical conclusions for correct pruning of unnecessary calculations and comparisons in each SD test, by which the efficiency of the SD tests can be improved. We make a comprehensive experimental study using real datasets to evaluate the effectiveness, efficiency, and scalability of the proposed algorithm.