The answer is no. Even the mean of a ration is not equal to the ratio of mean values of the two distributions. ... In most cases (including your case), people can just numerically calculate standard deviation of a
What happens when you divide by the standard deviation?
If you divide all the values by the standard deviation, then you will then have a distribution with a standard deviation equal to 1 (and so a variance equal to 12=1). The difference is that the mean is not 0, unless it was originally. You seem to be confusing the variance with (half) the range.
How do you divide values with standard deviations?
When you divide mean differences by the standard deviation you are standardizing the values. That is, you are expressing the values as deviations from the mean in standard deviation units (which are referred to as Z scores). As an example, say the mean of a data set is 50 with a standard deviation of 5.
