Collaborative filtering is the obvious way to make a scalable restaurant ratings service. Google tried to do it and apparently failed; then Yelp tried to do it [<a href="http:&#x2F;&#x2F;officialblog.yelp.com&#x2F;2013&#x2F;06&#x2F;whats-nearby.html" rel="nofollow">http:&#x2F;&#x2F;officialblog.yelp.com&#x2F;2013&#x2F;06&#x2F;whats-nearby.html</a>]. Not being a Yelp user myself, I don&#x27;t know if they are still doing this. Anybody have insight into whether Yelp is still personalizing recommendations or why personalization hasn&#x27;t worked in restaurants (in contrast to e.g., Netflix)?