This paper reports initial findings from a study that used quantitative and qualitative research methods and custom–built software to investigate online economies of reputation and user practices in online product reviews at several leading e–commerce sites (primarily Amazon.com).
M. Hu, and B. Liu. Proceedings of the tenth ACM SIGKDD international conference on Knowledge discovery and data mining, page 168--177. New York, NY, USA, ACM, (2004)