This episode looks at measures of spread, or dispersion, which we use to understand how well medians and means represent the data, and how reliable our conclusions are. They can help understand test scores, income inequality, spot stock...

This video provides an opportunity to create a Box and Whisker Plot. A pdf worksheet is available by clicking on the hyperlink at the bottom of the page. As you watch and listen to the teacher and student interact it helps clarify the...

This lesson will define the terms quartile, lower quartile, upper quartile, and interquartile range.

This video lesson demonstrates how to interpret box-and-whisker plots to find outliers.