Models and Managers: The Concept of a Decision Calculus

(This article originally appeared in Management Science, April 1970, Volume 16, Number 8, pp. B-466–B-485, published by The Institute of Management Sciences.) A manager tries to put together the various resources under his control into an activity that achieves his objectives. A model of his operation can assist him but probably will not unless it meets certain requirements. A model that is to be used by a manager should be simple, robust, easy to control, adaptive, as complete as possible, and easy to communicate with. By simple is meant easy to understand; by robust, hard to get absurd answers from; by easy to control, that the user knows what input data would be required to produce desired output answers;…