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Fundamentals of Sample Size Determination
podcast episode
A common question about reliability testing is, “What is the sample size?” It is also a difficult question to answer well. The right sample size balances cost, accuracy, and variability. In some cases, we also consider the time to results.
When planning reliability testing, an important task is to determine the necessary sample size. Too few samples and the results will be indistinguishable from statistical noise. Too many samples and the cost of testing becomes more than necessary.
Understanding the basics of sample size calculations for various situations and approaches permits you to quickly estimate the right sample size given the information you have available. The first estimate often leads to discussions concerning the constraints, goals, and striking the right balance of samples and outcomes.
Let’s discuss the many challenges and solutions available for sample size determination. We’ll examine a few situations, formulas, and best practices to determine the right sample size for each situation. Sample size starts as a statistical exercise and becomes a business/project conversation.
Learning to determine sample size is a critical skill for reliability professionals. Let’s talk about sample size determination and getting the fundamentals right.
This Accendo Reliability webinar originally broadcast on 15 May 2018.
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