Ask HN: How can I calculate a system-wide relative rating?

I have a web application with multiple tracking objects. These objects all have a many-to-many relationship to each other.

I need to create a rating system that provides a rating based on the combination of the relationships that each object instance has with other object instances - aka rating every instance of every object relative to one another based on their relationships with one another.

I've got some ideas but I'm keen to get some input before I commit any code.

Thanks HN community - you're awesome :)