Modelling schedule uncertainty in Microsoft Project 2010/2013 Microsoft Project 2010 (and 2013) no longer contain PERT charts. With this in mind, what is the recommended way to model uncertainty in project time estimates? **UPDATE** : I only brought up PERT diagrams because supposedly they were used for representing schedule uncertainty in the past. I don't really care about PERT diagrams. What is the best way to represent schedule uncertainty in Microsoft Project?

I emailed Steve McConnell, author of Rapid Development. He explained that the optimistic/pessimistic multipliers found in his book (table 8-1 "Estimate Multipliers by Project Phase") are meant to be applied on top of the "most likely" single-point estimate. In other words, say you have a total effort of 8 staff months and 6 months schedule, you end up with 2-32 staff months and 3.6-9.6 month schedule. You can apply the same logic to Microsoft Project. In my case I created a macro that multiplied the "Work" of all tasks by a factor of 0.25 or 4.0 and noted the resulting schedule.