Finding Active Expert Users in CQA System

Community Question Answering (CQA) system forms crucial part of the internet. Websites such as stack exchange, Quora, Reddit, etc helps lot of people. Experts in numerous fields are available to answer these questions. I still remember back in the early days of Quora, answers related to wikipedia were answered by Jimmy Wales (Founder of Wikipedia) himself. Given the large number of questions and users, it is important that each question is routed to the most suitable person. This ensures that the question is answered appropriately and within time.

The first challenge is to find expert users in the system. This is achived using topic-modelling techniques such as Latent Dirichlet Allocation (LDA). Just finding the expert users won’t work if the users are not active. The second part deals with finding the active users using time-series analysis. This can be extended to suggest the most appropriate time to route questions to a specific user.