The standard deviation formula may look confusing, but it will make sense after we break it down. In the coming sections, we'll walk through a step-by-step interactive example.

The formula we use for standard deviation depends on whether the data is being considered a population of its own, or the data is a sample representing a larger population.

A standard deviation close to 0 indicates that the data points tend to be close to the mean (shown by the dotted line). The further the data points are from the mean, the greater the standard deviation.

We learn how to calculate the mean and standard deviation of a discrete random variable. The concept of a random variable is explained, along with methods to calculate its expected value (mean) and …

Find the standard deviation of the data set. Round your answer to the nearest hundredth.

Standard deviation involves adding and subtracting values at various steps in the calculation process. For example, the differences between each data point and the mean are calculated, squared, …

Practice calculating and interpreting the mean and standard deviation of a discrete random variable.

Sal shows an example of calculating standard deviation and bias. Created by Sal Khan.

The standard deviation (sigma) is a measure of how much the data is spread out around the mean, not a better guess as to what the mean should be. A small value of sigma indicates that you don’t need to …

Standard deviation measures how far apart numbers are in a data set. Variance, on the other hand, gives an actual value to how much the numbers in a data set vary from the mean.