An empirical analysis of software effort estimate alterations

This research studies the effect of descriptive estimate alterations on the accuracy of the resulting estimate. The two major reasons for estimate alterations studied here are the project manager's experience and time constraints. Estimate alterations done for these two reasons and their effect on accuracy is also examined. The confidence of the project manager in the estimation model and its effect on the accuracy of the resulting estimate is also studied. The extent of estimate alterations, estimate alterations made for these two reasons, and the project manager's confidence significantly affect the accuracy of the resulting final estimate. Finally, the reasons reported by managers to explain the percentage of relative error in software effort estimation are documented.