Yelp Events: Making Bricks Without Clay?

Review based geosocial networks are online social networks centered on the location of venues and users as well as on reviews left by users for visited venues. The popularity and impact of reviews makes them an ideal tool for influencing public opinion. In this paper we study the effects of Yelp Elite events, organized for the benefit of Elite reviewers, on the image of the hosting venues. To this end, we introduce tools for identifying venues receiving abnormally large numbers of reviews in a short time and use them to detect correlations between events and hosting venues. We have implemented a browser plugin that makes users aware of Yelp event manipulations. We use data we collected from Yelp to show that Elite events have a noticeable short-term impact on the rating of hosting venues.