Tag: sigma

Sigma is the eighteenth letter of the Greek alphabet and is used as a common notation in statistics as a measure of summation and variation.

Learn the benefits of tracking sigma level, including how it is used to understand how the current quality capabilities match with customer expectations, where future process improvement opportunities lie, and how to verify results.

This paper looks at some of the methods of estimating standard deviation (which I will usually refer to as ‘sigma’). Additionally, I propose a new formula for estimating sigma for small sample sizes and also present a means to mathematically evaluate these competing estimates of sigma. The question was posed to me: “I have five […]