it is easy to calculate the average or mean production. You just add up the three means and divide by three. But what if I want the average standard deviation of the three machines? The pooled ...

Investors often use standard deviation to quantify asset volatility. You can calculate standard deviation of an asset in a spreadsheet with a series of daily closing values. Standard deviation ...

So the more spread out the group of numbers are, the higher the standard deviation. A variance is the average of the squared differences from the mean. To figure out the variance, calculate the ...