One of the comments on the blog perfectly sums up what would have been my hypothesis, so I will simply repeat it here: Part of the drop may be due to Group

One of the comments on the blog perfectly sums up what would have been my hypothesis, so I will simply repeat it here: Part of the drop may be due to Groupon inducing people to visit a business selling something they otherwise wouldn't be interested in. E.g., I might check out a Greek restaurant even though I'm indifferent to Greek food because of a good deal and curiosity. Given the same experience as someone who likes the cuisine, I might then give a lower rating. - Anonymous http://mybiasedcoin.blogspot.com/2012/03/groupon-effect-on-yelp-ratings-guest.html?showComment=1333075513809#c8753365250508256036 http://mybiasedcoin.blogspot.com/2012/03/groupon-effect-on-y...