  The proliferation of Web services makes it difficult for users to select the
most appropriate one among numerous functionally identical or similar service
candidates. Quality-of-Service (QoS) describes the non-functional
characteristics of Web services, and it has become the key differentiator for
service selection. However, users cannot invoke all Web services to obtain the
corresponding QoS values due to high time cost and huge resource overhead.
Thus, it is essential to predict unknown QoS values. Although various QoS
prediction methods have been proposed, few of them have taken outliers into
consideration, which may dramatically degrade the prediction performance. To
overcome this limitation, we propose an outlier-resilient QoS prediction method
in this paper. Our method utilizes Cauchy loss to measure the discrepancy
between the observed QoS values and the predicted ones. Owing to the robustness
of Cauchy loss, our method is resilient to outliers. We further extend our
method to provide time-aware QoS prediction results by taking the temporal
information into consideration. Finally, we conduct extensive experiments on
both static and dynamic datasets. The results demonstrate that our method is
able to achieve better performance than state-of-the-art baseline methods.
