Superstore data: standard deviation

When you have a normal distribution, about 68% of your data lies within the width of two standard deviations from the mean (one standard deviation on each side). However, when you have many outliers (your distribution is leptokurtic), the interquartile range (IQR), holding 50% of your data, is a better measure of spread, since it isn't influenced by the extreme values. The Summary Card contains information about the spread of your data in the form of the standard deviation (SD), first, and third quartile. Use the Summary Card to compare SD and IQR of the profit data.

If you lost progress, load the workbook 2_2_stdev.twbx from the Workbooks folder on the Desktop.