Standard error of mean
Used as an indication of the reliability of x-bar as an estimate of the mean of the population. Smaller numbers mean the estimate of the population average has less variability. To calculate, use the standard error formula below.
![images\ebx_-2138538623.jpg](../../images/ebx_-2138538623.jpg)
where N is the total number of observations, and σx is the Population Sigma .
Learn more about the Statistical Inference tools
for understanding statistics in Six Sigma
Demystified (2011, McGraw-Hill) by Paul Keller,
in his online Intro. to Statistics short course (only $89)
or his
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