## Completing a Statistical Sampling

Statistical sampling is the process of choosing a percentage of results at random. For example, a project creating a medical device may have 20 percent of all units randomly selected to check quality. This process must be completed on a consistent basis throughout the project, rather than on a sporadic schedule.

Figure 8-5

A Pareto diagram is a histogram that ranks the issues from largest to smallest.

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100%

100%

I500 !000 SOO O

I500 !000 SOO O

 2!- 28- 29- 3!- !- 3- 9- 12- !3- 14- 17- 24- 26- 27- 3O- 3- 12- !3- 15- 16- 19- 20- 22- 26- 27- 28- 4- Au Au Au Au Se Se Se Se Se Se Se Se Se Se Se Oc Oc Oc Oc Oc Oc Oc Oc Oc Oc Oc No Series! -32 -2! -60 -3O 2SS -7S 6OO -!O -4O -26 -28 -SO 6O -3O -!O -3O -26 -6O -!O 100 -60 102 650 300 -82 -90 350

Figure 8-6 Run charts track the results of inspections over time.

Figure 8-6 Run charts track the results of inspections over time.

Statistical sampling can reduce the costs of quality control, but mixed results can follow if an adequate testing plan and schedule are not followed. The science of statistical sampling (and its requirements to be effective) is an involved process. There are many books, seminars, and professionals devoted to the process. For the Certified Associate in Project Management (CAPM) and PMP exams, know that statistical sampling uses a percentage of the results to test for quality. This process can reduce quality control cost.

## Project Management Made Easy

What you need to know aboutâ€¦ Project Management Made Easy! Project management consists of more than just a large building project and can encompass small projects as well. No matter what the size of your project, you need to have some sort of project management. How you manage your project has everything to do with its outcome.

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