How do I combine standard deviations of two groups?
Oct 26, 2018 · I know the means, the standard deviations and the number of people. I don't know the data of each person in the groups. Group 1 : Mean = 35 years old; SD = 14; n = 137 …
Standard deviation sig figs - Mathematics Stack Exchange
Let's say I calculated a mean to be 2.475, but the data values had the least significant figure in the tenths place (i.e. 2.6, 2.8 etc.) so I round the mean value to 2.5 for correct sig figs. Howev...
Why is variance squared? - Mathematics Stack Exchange
The mean absolute deviation and standard deviation measure the same thing (notice the similarity of their names). The variance is convenient because it satisfies the property that the variance …
Does standard deviation change if multiplied by a constant? or if a ...
The standard deviation is a measure of "spread", i.e. how far values vary from the mean. Adding the same fixed number to each output changes the "location" of each data point, but it doesn't …
statistics - What situation calls for dividing the standard deviation ...
In the normal distribution, if the expectation of the average of a sample size n is the same as the expectation, however, the standard deviation of your sample is to be divided by the square …
Can I calculate the new standard deviation when adding a value …
Can I calculate the new standard deviation when adding a value without knowing the original set of values? Ask Question Asked 11 years, 6 months ago Modified 11 years, 6 months ago
probability - Unit Conversions with standard deviation
Nov 19, 2020 · 0 When converting units of standard deviation, should I do the calculations in variance then convert the variance back? For reference, I am trying to convert the standard …
How to determine if Standard Deviation is high/low
What does the standard deviation say about the response time data distribution? When you say low/high standard deviation, what does this actually mean? Is this in comparison to the …
Why are correlation and standard deviation unitless?
Sep 10, 2019 · Its not really obvious as to why taking the square root of the variance produces the standard deviation and why is it unitless, and why does dividing the covariance by the product …
statistics - Why do we calculate variance if standard deviation …
Jan 27, 2022 · The standard deviation approximates a typical element's distance from the mean (as you pointed out), so it's useful for visually understanding a distribution, whereas the …