Star rating of pictures

Looking around at pictures, it seems that if a picture gets at least 3 or more 5-star comments, the overall rating for the picture is 5 stars.

This is not the case for one of my pictures, which has 4 5-star comments, but only 4 stars overall. Has anyone else had this happened on any pics?

 Can you clearify the rules please POE? 

Hi David.

Our site uses the Bayesian method. It's a complicated technique called Bayesian weighting and is used by a lot of the big sites to give more of a 'true' rating. The biggest movie site on the internet (IMDB) uses it to rate their movies: Click here for more info on how they use it.

We also use it, but the calculations are slightly different based on our member numbers etc, but the main thing is how many ratings the image gets. For instance, an image that receives a 5-star rating from just 2 members, is rated less than an image that gets a 4-star rating from say 10 members, as 10 votes carry more weight than just 2 votes. I hope that makes sense. There is lots of info available on the web about it. Here is another link describing how it works.

Chris & Sarah