Amazon accumulates user reviews in public user profiles: Specifically, Amazon marketplace encourages the buyers to rate their products and write qualitative reviews to describe their experience. There are several incentives for a user to write such reviews. First, users write reviews on e-commerce sites hoping that it would help others understand what to expect from the product [14]. Second, some users write reviews to gain the appreciation of other users.Third, some users write them for self-validation. The last two reasons are perhaps also acknowledged by Amazon.