As such, we decided upon a simple set of metrics that best approximated real-world threats, that is, to try to test for attacks actually used by attackers.
Warhol prided himself on speed of execution and approximated that of one of today's electronic-options trading houses. (I'm exaggerating.) I bought this piece in the early '80s and used it as our corporate logo.
The book is a tour de force, showing, for example, how the potential contribution of biofuels can be approximated from just three numbers: the intensity of sunlight, the efficiency with which plants turn that sunlight into stored energy and the available land area in Britain.