Strong Social Component-Aware Trust Sub-network Extraction in Contextual Social Networks

In Online Social Networks (OSNs), the important participants, the trust relations between participants, and the interaction contexts between participants greatly impact a participant's decision-making in many applications, such as service provider selection and crowdsourcing service invocation. However, predicting the trust between two unknown participants based on the whole large-scale social network can lead to very high computation costs. Thus, prior to trust prediction, extracting a small-scale sub-network containing the important participants and the corresponding contextual information with a high density could make the trust prediction more efficient and effective. However, extracting such a sub-network has been proved to be an NP-Complete problem. To address this challenging problem, we propose a strong social component-aware trust sub-network extraction model, So-BiNet, to search for near-optimal solutions effectively and efficiently. Our method can extract a trust sub-network without any decompression, which can in turn greatly save the search time of trust sub-network extraction. The experiments, conducted on four social network datasets, demonstrate that our approach can efficiently extract sub-networks covering important participants and contextual information while keeping a high density. Our approach is superior to the state-of-the-art approaches in terms of the quality of the sub-networks extracted within the same execution time.