I'd say this is a must-read about how Yelp's review filter can completely miss the real reviews and reward the fake ones.

Just to be clear, 10 honest one star reviews have been hidden from public view. That’s a 71% false positive hit rate.

So why did Yelp get it wrong 10 times?In each case the one star review was left by someone who would never normally leave a review… they were simply so outraged that they were motivated to signup to Yelp and try to warn others how bad this company is. None of them ever used Yelp again. Furthermore, they didn’t have the knowledge or inclination to try to make their Yelp profile look acceptable to Yelp’s automated suppression systems.
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