文摘
Community Question Answering (CQA) systems (e.g. StackOverflow) have gained popularity in the last years. With the increasing community size and amount of user generated content, a task of expert identification arose. To tackle this problem, various reputation mechanisms exist, however, they estimate user reputation especially according to overall user activity, while the quality of contributions is considered only secondary. As the result, reputation usually does not reflect the real value of users’ contributions and, moreover, some users (so called reputation collectors) purposefully abuse reputation systems to achieve a high reputation score. We propose a novel reputation mechanism that focuses primarily on the quality and difficulty of users’ contributions. Calculated reputation was compared with four baseline methods including the reputation schema employed in Stack Exchange platform. The experimental results showed a higher precision achieved by our approach, and confirmed an important role of contribution quality and difficulty in estimation of user reputation.