if the formula is valid with a nonnormal distribution, can you use it for control charts? what formula for normal distribution in a sample how to figure out the variances of sigma in a non normal distribution? if you use the deviation in bootstrapping, is this formula valid for normal or non normal distributions? can you find non normal sqrt data by bootstrapping what is the cte of the equation if a normal distribution is not valid a regression should be used can you calculate the trimmed mean in normal distributions? why is sigma calculated what is the deviation in a standard deviation equation can you use the te$ to find the normal distribution of a distribution in a sample? how to use sigma chart in a regression what is the normal deviation of a test in mri what is normal for sigma in a graph can we use an equation that does not require a variance to be valid? is the sigma formula valid what is the metric used to figure a normal distribution of population how do you find the trimmed mean in sigma? when using a sampling sample do you need to know the deviation value for the test? is sigma valid with normal distributions