Exploiting Content Quality and Question Difficulty in CQA Reputation Systems

  • Adrian Huna
  • Ivan SrbaEmail author
  • Maria Bielikova
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 9564)


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.


Community Question Answering User reputation Expertise estimation 



This work was partially supported by grants. No. VG 1/0646/15, VG 1/0774/16 and KEGA 009STU-4/2014 and it is the partial result of collaboration within the SCOPES JRP/IP, No. 160480/2015.


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Copyright information

© Springer International Publishing Switzerland 2016

Authors and Affiliations

  1. 1.Faculty of Informatics and Information TechnologiesSlovak University of Technology in BratislavaBratislavaSlovakia

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