Have you noticed the latest trend in the world of shopping and commerce? A few years ago, companies were encouraging us to like them on Facebook or follow them on Twitter. (They still do today, though not as often given that avid internet users know by now that virtually every business has jumped on the social media bandwagon.) Now, they're pushing us to review them on sites like Yelp. But, as the saying goes, they ought to be careful what they wish for. I have had unpleasant experiences at various restaurants and retail establishments in the past year, and I've had no qualms about airing these sentiments on said websites. In fact, many consumers are more inclined to rate and review a company following a bad experience than a favorable one. A preponderance of either negative or positive reviews, however, should raise red flags. For example, a disproportionate number of 5-star reviews coming from accounts with only one or two reviews to their name means something i...