Page 79 - The Six Sigma Project Planner

Worksheet 25. Statistical Analysis of Project Duration

Lower 95% Upper 95%
Path Mean Variance Sigma
Estimate Estimate

Project Due Date

Expected Project Completion Date

Standard Deviation of Project Completion

95% Lower Confidence Interval (expected
completion date minus two standard deviations)
95% Upper Confidence Interval (expected
completion date plus two standard deviations)
Probability of Meeting Due Date

If the probability of not meeting the due date is high, the deadline should be discussed
with the project sponsor. In some cases it is necessary to modify the project’s charter,
assign additional resources, etc.

Using Simulation to Analyze Project Schedules
The analysis conducted above involves a number of simplifying assumptions and
approximations. In most cases, the accuracy of the results will be more than adequate.
However, it is possible to conduct a more precise analysis using computer simulation.
®
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The example here uses the program Crystal Ball (CB).

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Available from Decisioneering, Inc., www.decisioneering.com.

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