||The recent online social network tools and services on the Internet are extremely popular. Through the online social networks, users can create personal online communities in which users can interact with each other of the same interest. Instant Messenger (IM) can also be regarded as one of social network services. In IM, each user can build the list of contacts such that two or more persons in the list can initialize instant text messaging, voice chatting and file transfering. The Instant Messenger network is one of the largest digital social networks with a lot of online human resources. In daily life and work, we often face many questions (problems), and/or have interest in something unknown. We would like to know the answers to the questions or consult the suggestions of others. Although search engines, web-based forums, and inquiries to friends via e-mails or instant messenger are all methods we can use today for seeking answers to the questions, in many cases, much time is still spent to search, organize, or wait for responses. If knowledgable online IM user can be handily found to answer questions in real-time, then the time spent to browse webpages, wait for forum responses, or inquire may be dramatically reduced. In this thesis, we propose an answer-finding system (IM Finder) that helps people accurately find knowledgable online users to answer questions in real-time via the social network based on Instant Messenger’’s contacts. Users share successful experiences of finding responders to achieve greater efficiency when seeking answers to questions. System relies on similarity measures between historic and new questions asked, and the trust among mutual friends, to provide timely and accurate mechanism of multi-hop question relay through contacts to find appropriate IM online users to answer questions interactively.|
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