# Video and Multimedia

Click on the following links. Please note these will open in a new window.

## Video Clips

How to (Really) Calculate the Standard Deviation
Short video example of how to calculate the standard deviation (2:05).

What is Variability?
This video discusses variability, range, interquartile range, semi-interquartile range, variance formulas, standard deviation, normal distributions, and an example (6:55).

Estimate Population Variance
This video provides an example of how to estimate the variance of a population by looking at the data in a sample (10:37).

Probability Using the Empirical Rule
This video illustrates the Empirical Rule and what it means when applying it to an example (4:59).

## Audio Clips

What Are the Range and Standard Deviation?
This podcast describes range and standard deviation by discussing an example of students’ math scores (7:21).

Are Recent Heat Waves a Result of Climate Change?
An NPR interview discusses standard deviation as a “measure of abnormality” and how this is used to describe extreme climate change that the United States is currently experiencing (3:12).

Suicides Rise in Middle-Aged Men, And Older Men Remain at Risk
Describes disproportionate impact suicide has on men and the group who has the highest rate of suicide (4:13).
Also includes link to the “Death Rates for Suicide, by Sex, Race, Hispanic Origin, and Age: United States, Selected Years 1950–2010” table.

## Web Resources

Measurement of Uncertainty: Standard Deviation

Provides description and example of how to calculate standard deviation.

Variability Simulation
An online simulation illustrates how changes in the mean and standard deviation affect the position and shape of the distribution.

Interquartile Range in Statistics
This article describes interquartile range including what it is, how to find it, what it is used for, and its history. Also includes a video on the website that calculates an example.

Sample Variance
This article provides a more in-depth explanation of why the sample variance has n – 1 in the denominator.