### Effect of Statistical Distributions on Success Rates

Posted:

**Fri Dec 23, 2016 12:07 pm**Does the type of statistical distribution matter when we calculate success rate due to deadline?

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Posted: **Fri Dec 23, 2016 12:07 pm**

Does the type of statistical distribution matter when we calculate success rate due to deadline?

Posted: **Fri Dec 23, 2016 12:14 pm**

Yes, the success rate can be affected if the distributions have significantly different probability density at the deadline. In the example below, there are two tasks with the exact same estimates, but the statistical distributions are different: Triangular and Uniform with deadlines set at 6 days, one more than the base estimate of five. We can see that Task 1 has a much higher success rate than Task 2. This is because the probability or area under the curve at ≥ 6 days is greater with the Uniform Distribution and therefore the success rate of finishing at or before 6 day duration is less for Task 2.

Statistical distribution for duration for task 1 is Trangular.

Statistical distribution for duration for task 2 is Uniform

Statistical distribution for duration for task 1 is Trangular.

Statistical distribution for duration for task 2 is Uniform