Mohammad Taghi Hajiali - Department of Industrial Engineering, Faculty of Industrial Engineering, University of Science and Technology, P.O.Box: ۱۶۸۴۶, Tehran, Iran
Kamran Shahanaghi - Department of Industrial Engineering, Faculty of Industrial Engineering, University of Science and Technology, P.O.Box: ۱۶۸۴۶, Tehran, Iran

One of the main challenges facing project managers is the evaluation of project progress and its earned value as well as the estimation of cost and time in project completion. In this paper, we attempt to develop a method which is based on confidence limits. The proposed method is of two approaches which distinguish the risks of activities implementation and the critical path in determination of confidence interval for completion cost and time. The above approach has applied a p-factor for weight determination in confidence intervals. In the final part, we will discuss the ways of applying these proposed methods and their importance with an example and also demonstrate the superiority of the above methods over the unmodified ones in a confidence interval.

Earned Value, Confidence interval, Critical Path, P-factor, Completion Cost, completion time