A paradox for trust and reputation in the e-commerce world

Trust and reputation systems are widely adopted in the e-commerce environment to help buyers choose trustworthy sellers. It is a normal thought that the higher the reputation is, the more trustworthy its holder should be. However, our research discloses that under certain circumstances, a high-reputation seller has greater intention to cheat, which means that buyers should trust the low-reputation sellers better in those cases. We term this phenomenon Trust- Reputation Paradox. The theoretical proof, based on the game theory, is conducted to show the existence of the paradox. The root causes of this abnormality are revealed and discussed. In the end, we provide some guidelines for trust and reputation system designers to avoid this obscure pitfall.