Simulation results on project completion time

According to the PERT method, a project length is normally distributed with a mean equal to the mean of the critical path. The expected length of the critical path is the sum of the expected activitiespsila durations of that path. Risks, as a result of project delays are calculated based on the normal approximation to the project length. During the course of our research, we realized that in many cases the conditions of the Central Limit Theorem are not satisfied; hence, the project completion time is often not normally distributed. In other words, the expected project completion time is greater than the sum of the activitiespsila duration along the critical path. We analyzed project completion time using both the analytic approach and simulation. Our results show that in many cases it is biased to use the critical path length when attempting to estimate project completion time. The results of the current study provide users with better estimates and upper bound to the project completion time. These results can be used to improve risk management programs.