Craig Brown (a must read Blog) posted a quote
The trouble with the world is that the stupid are cocksure and the intelligent are full of doubt. — Bertrand Russell.
This is a powerful concept. In our commercial practice, there is rarely a discussion of "probability," since commercial managers seem to seek certainty.
In the defense world, there is an official framework - Probability of Program Success (PoPS).
Search Google for "probability of program success." The majority are at the Defense Acquisition University (DAU) site. Read how statistical probability, stochastic processes for cost, schedule and technical performance measures are the semantics of normal programs.
Here's a direct link, answer yes to the certification warning. Many .mil sites do this if you're missing the cert.
