What is standard deviation?

A measure of spread: the square root of the average squared distance from the mean.

Sample vs population?

Use population when you have all data; use sample when data is a sample of a larger group (divides by n-1).

Calculate mean, variance, and standard deviation (sample or population) from a list of numbers.

Numbers (comma or space separated)Population (not sample)

What is standard deviation?: A measure of spread: the square root of the average squared distance from the mean.
Sample vs population?: Use population when you have all data; use sample when data is a sample of a larger group (divides by n-1).

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