How does the thread ratings come about?

[QuarterMillionMan]

I was curious how the thread ratings gets assigned? Some threads have up to 5 stars. Does it get activated by the number of views? Or some other criteria?

[bjl584]

Anyone can do it. I just gave this thread 5 stars as an example. Click on the rate thread icon in the upper right hand corner of the thread and it will let you rate it.