11. A computing device, comprising: a communication device configured to: receive questions and answers, each question having one or more answers, and each question and each answer being associated with a particular user; and receive evaluations of the answers from users; and one or more processors configured to: identify at least one of textual and contextual features for each answer to obtain sets of features; generate a user preference graph indicating relationships between users associated with at least one of the questions, the answers, and the evaluations; determine a measure of deceptiveness for each answer based on its set of features and the user preference graph; and detect whether each answer is a deceptive answer by comparing its measure of deceptiveness to a threshold indicative of deceptive answers.
11. A computing device, comprising: a communication device configured to: receive questions and answers, each question having one or more answers, and each question and each answer being associated with a particular user; and receive evaluations of the answers from users; and one or more processors configured to: identify at least one of textual and contextual features for each answer to obtain sets of features; generate a user preference graph indicating relationships between users associated with at least one of the questions, the answers, and the evaluations; determine a measure of deceptiveness for each answer based on its set of features and the user preference graph; and detect whether each answer is a deceptive answer by comparing its measure of deceptiveness to a threshold indicative of deceptive answers. 14. The computing device of claim 11 , wherein the evaluations indicate at least one of (i) a best answer for a specific question, (ii) an indication that a specific answer is helpful, and (iii) an indication that the specific answer is not helpful.