And to add to the point above, Yelp ratings are not well-normalized across markets. The things that people care about in the 'burbs is different than in the city and places get voted up or down for odd reasons.

For example, Joya in Palo Alto is a pretty amazing restaurant but only gets 3.5 stars. The Cheesecake Factory (which is a pretty crappy chain) gets a 5. This is not really good data.