Have you ever used the standard deviation formula to calculate the difference between the planned and the executed dates? To produce input for the weekly status report.
I found a PM using that, and was very surprised since I have used that only for estimating duration (like 3-point estimate technique).
Rami/Maen, Let's say that the project change the finish date two times (due delays, etc.), and they use the original date scheduled to finish the project with the others two and calculate the standard deviation, the resulting number they take as the schedule variance (time deviation of the project) Saving Changes...
Shobhit, that formula is the one I know and I have used for estimation.But my question is using the SD for schedule variance calculation. Saving Changes...
Sergio Luis ConteHelping to create solutions for everyone| Worldwide based OrganizationsBuenos Aires, Argentina
Schedule variance can be calculated in other way. See the Earned Value Formulas and its adaptation to use time instead of cost. I ever used the standard deviation as you Engels when estimating activities. Is the first time I see somebody to use it for that purpose. But if it could be used to communicate something needed to the stakeholders it is welcome the method. I will think about if it is use for me or not. I have used a montecarlo simulator as a plag-in for MS Project. In that case, the simulator calculated what you state for each task and the whole schedule if you want. The problem with that, in my case, is you have to consider the probability distribution for each activity and it has no sence in the environments where I have been working. Saving Changes...
Standard deviation concept can be applied in analyzing the schedule variance. In addition to monitoring the "Trend" of deviation of project progress with respect to schedule baseline, standard deviation helps to provide a "single measure / value (sigma) " to answer actual progress so far deviated from baseline & definitely helps in determination of likely delay in future. Of course, there are several factors / constraints which can limit SD application. Saving Changes...
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