Table of Contents
Does the standard deviation change if the mean changes?
SD will change by that same number. The mean will also change by the same number. If every term is doubled, the distance between each term and the mean doubles, BUT also the distance between each term doubles and thus standard deviation increases. If each term is divided by two, the SD decreases.
How does mean impact standard deviation?
The further the data points are from the mean, the greater the standard deviation.
When the mean increases the standard deviation?
Thus, the average distance from the mean gets bigger, so the standard deviation increases. When each term moves by the same amount, the distances between terms stays the same. The mean moves up to 14.5, but the distances don’t change, meaning that the standard deviation stays the same.
What happens to the mean and the standard deviation of a set of data when the value of each datum is increased by the same amount?
As a general rule, the median, mean, and quartiles will be changed by adding a constant to each value. Adding a constant to each value in a data set does not change the distance between values so the standard deviation remains the same.
What happens to standard deviation when mean decreases?
Thus, the average distance from the mean gets smaller, so the standard deviation decreases. When the largest term increases by 1, it gets farther from the mean. Thus, the average distance from the mean gets bigger, so the standard deviation increases. Since the terms are farther apart, the standard deviation increases.
What factors affect standard deviation?
The standard deviation is affected by outliers (extremely low or extremely high numbers in the data set). That’s because the standard deviation is based on the distance from the mean. And remember, the mean is also affected by outliers. The standard deviation has the same units of measure as the original data.
What does it mean when the standard deviation is higher than the mean?
A standard deviation (or σ) is a measure of how dispersed the data is in relation to the mean. Low standard deviation means data are clustered around the mean, and high standard deviation indicates data are more spread out.