The question is a bit of a red herring. By all means, get rid of unproductive and troublesome employees. But if you try to use age as a simplistic predictive proxy for productivity or attitude, I think evidence shows that you'll fire a lot of the wrong people, as well as court the wrath of labor attorneys.
I think you were thinking of inversely proportional.
Searching Wikipedia, inverse correlation is also valid but I've always heard it called indirect or negative.
I knew what you meant and you were on the right track.
No.
> But if you try to use age a simplistic predictive proxy...
Well, that is obviously the wrong thing to do, but I am not sure how that relates to my question.