Return on Software: Maximizing the Return on Your Software Investment

Summary

This chapter showed several different methods, both ineffective and effective, to allow for inaccuracy in estimates. Two fairly common approaches, increasing the MARR and shortening the planning horizon, are not always effective. Both of these methods assume that safety is achieved by using more conservative decision criteria, thereby penalizing the more uncertain alternative. This chapter showed that, in fact, the assumed margin of safety isn't always there.

Three less common approaches are far more effective:

• A more rational approach to addressing inaccuracy in estimates is to consider a range of estimated values. The estimator is asked to create three separate estimates for each factor: optimistic, most likely, and pessimistic. Instead ...