[VinnieC]

Another thing to keep in mind is a person's VPIP when looking at their aggression factor (or frequency).

A person with a VPIP of 50%, but with an aggression factor of 2 is probably a maniac. But someone with a VPIP of 12% and a AF of 2 is quite passive.

In practical terms, it means the guy who has a VPIP of 50% (who has a wide range of starting hands) is raising the same ratio of times as the guy who only has a VPIP of 12% (and is only playing premium hands).