Trusted QoS Service Selection Based On The User Preferences

With the continuous development of the Internet and e-commerce technology, more and more users and services are involved in service computing. It is increasingly important to select the service really satisfying user’s requirement from the mass services. Trusted QoS achievement is a key step in the service selection process, which attracts attention from more and more researchers. Little current research take the user preference into account of getting trusted QoS, which makes it harder to provide reliable reference to select a service for a certain user.To solve the above problems, a trusted QoS service selection method based on the target user’s preference is studied in this paper. Based on definitions on the service multi-attribute rating and the preference of the target user, the deviation to average ratings is computed for each previous user to evaluate his/her trusted degree to target user. If the deviation exceeds a certain threshold, the previous user is recorded once, when the number of being recorded reaches another given threshold, the previous user is removed out. The final remaining users after an iterative execution are considered as trusted users who can provide reliable reference. Then a benchmark evaluation vector for a candidate service is obtained based on the trusted user’s service evaluation. The similarity between an evaluation from a trusted user and the benchmark of a candidate service is computed, based on which a comprehensive evaluation vector of a candidate service is achieved. Then the satisfaction of the trusted users on QoS attribution of a candidate service is evaluated. The comprehensive evaluation vector of the candidate services is transferred into a final score based on the satisfaction and the target user’s preference. The candidate service with highest score is determined as the selected one for the target user. A case study is used to illustrate the method and the simulation result shows its effect.