Brian Dunning's FileMaker Custom Functions

ThreePoint ( Optimistic ; Pessimistic ; MostLikely )

One of the blessed expected value estimation calculation formulas for the PMP is the three point estimate.

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Dwayne Wright   Dwayne Wright

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  Sample input:
ThreePoint ( 40 ; 120; 50)
  Sample output:

  Function definition: (Copy & paste into FileMaker's Edit Custom Function window)

One of the blessed expected value estimation calculation formulas for the PMP is the three point estimate. What it does is take three estimation points and gives you a most likely result. It can be used to calculate time for schedules or money for budget estimates.

Say that a client is asking for an estimate of hours to do a project task. You have done this type of work before and have code you can apply to it. You feel pretty confident that you can do the job in 50 hours and perhaps as low as 40. You want to throw in a higher estimate because you might not have all the deliverable scope because the client isn’t that sure about their definitive needs. So you put in a high estimate of 120 hours into the mix.

You could tell the client that it could take anywhere from 40 to 120 hours. This might be a way to get them to better define their scope to you. It also may be a way to ensure that you never hear from the client again. A three point estimate says that if you give them an estimate of 60, you are pretty well covered.

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andrew   andrew, Namibia
Sep 25, 2014
your answer is not helpful at all, when one visit yo site he/she expect example not jus formulas.
wen dealing with figures u suppose to give examples so as to make it easy for your readers to have a more clear pict

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