Abstract: Trust and reputation are decisive factors in internet service provision. The concept is to let the parties rate each other. Reputation models used in e-commerce have the main intention to guide the customers or buyers in a proper way so that they can choose between the different available trustworthy sellers. The models are meant to project the different sellers as per their services and quality. Models are a real need because most of the e-commerce systems have different qualities. But models differ between each other by the methods they opt to calculate the trustworthiness measure for different sellers. Based on such calculations the ranking of the sellers will also vary. Feedback mining method of trust calculation outperforms all other methods with the idea that users are free to express themselves in textual feedback comments. The method addresses the issue of positive bias which has become a major concern nowadays in the field of e-commerce.

Keywords: reputation system, feedback mining, trust score, positive bias, opinion extraction