Ratings on the internet (on Amazon, Netflix, IMDB, etc.) can be very valuable, but there are also big problems with them that people aren't as aware of as they should be. Here, I'll discuss two major issues with online ratings. Problem 1: The Different People Problem Probably the biggest problem with ratings is that the different people rate different sorts of products. In other words, the people that rate The Selfish Gene (4.5 stars on Amazon) are a somewhat different group of people tha...