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amazon reviews lawsuit example
It is hard to say without knowing their techniques. The problem with this task is that there is often no hard proof that the detection is actually correct unless the author of the actual fake reviews (not made up fake reviews) from a review hosting site confirms it. Of course, it is easier if the company actually hosts reviews (e.g., Amazon or Yelp) because they can analyze the public information that the general public can see and also (more importantly) their internal data which tracks all the activities after a person comes to the website. A lot of unusual behaviors can be detected. Unfortunately, such data is not available to people outside the site.
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