I'm not an expert with mathematics so I hope I'm posting in the right place!
I've got a lot of products which can be rated good, bad and OK by a user. What I'm having trouble with is finding which is rated the "best"- similar to Amazon's sort by rating.
Getting the average rating won't work as I want a product with 99 good ratings and 1 bad rating to rank higher than a product with just 2 good ratings. Any ideas on what type of formula to use?
ANSWER, SORT OF:
Thanks to Raskolnikov's comment I've found out what I need is either the Wilson Score Interval (which at the minute is way too complicated) or the Bayesian rating, which can be found here- http://www.thebroth.com/blog/118/bayesian-rating.
Now I know at least what the formula I want is called, I can figure out how to get what I want.