Privacy support
You could for example apply a simple data mining privacy preserving approach to your database ratings to a small extend (e.g 10%).
This might bring lower accuracy. However users mights give more ratings freely.
1
vote
![](https://secure.gravatar.com/avatar/7de9c81b7f70472729e99756b17e10b5?size=40&default=https%3A%2F%2Fassets.uvcdn.com%2Fpkg%2Fadmin%2Ficons%2Fuser_70-6bcf9e08938533adb9bac95c3e487cb2a6d4a32f890ca6fdc82e3072e0ea0368.png)