A Simple CPM Time-Cost Tradeoff Algorithm

Abstract

This article describes an algorithm for efficiently shortening the duration of a project when the expected project duration exceeds a predetermined limit. The problem consists of determining which activities to expedite and by what amount. The objective is to minimize the cost of the project. This algorithm is considerably less complex than the analytic methods currently available. Because of its inherent simplicity, the algorithm is ideally suited for hand computation and also is suitable for computer solution. Solutions derived by the algorithm were compared with linear programming results. These comparisons revealed that the algorithm solutions are either (a) equally good or (b) nearly the same as the solutions obtained by more complex analytic methods which require a computer. With this method the CPM time-cost tradeoff problem is solved without access to a computer, thereby making this planning tool available to managers who otherwise would find implementation impractical.