Abstract
Online discussion forums provide knowledge sharing facilities to online communities. Usage of online discussion forums has increased tremendously due to the variety of services and their ability of common users to ask question and provide answers. With the passage of time, these forums can accumulate huge contents. Some of these posted discussions may not contain quality contents and may reflect users' personal opinions about topic which may contradict with a relevant answer. These low quality discussions indicate the existence of unprofessional users. Therefore, it is imperative to rank an expert in online forums. Most of the existing expert-ranking techniques consider only user's social network authority and content relevancy features as parameters of evaluating user expertise. But user reputation as a group member of thread repliers is not considered. In this context a novel solution of expert ranking in online discussion forums is proposed. We proposed two expert ranking techniques: The first technique is based on user and their co-existing user's reputation in different threaded discussions, and the second technique is based on user answers' quality and their category specialty features. Furthermore, we extended a technique expertise rank with our proposed features sets. The experimental study based on real dataset shows that the following proposed techniques perform better than existing techniques.