Tuesday, August 21, 2007

Box and whisker plots

You collected data today in class and we talked through the processes of finding the five number summary and constructing a box and whisker plot for univariate quantitative data.

5 number summary: Min, Q1, Med, Q3, Max

Use the 5 number summary to construct the box and whisker plot. Use the interquartile range (the length of the box containing the middle 50% of the distribution)to determine whether observations are outliers. The boundaries of reasonable answers are Q1 - 1.5(IQR) and Q3 + 1.5(IQR).
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For homework, construct the modified box and whisker plot for your data.
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There are many websites that explain how to perform this task.
http://www.statcan.ca/english/edu/power/ch12/plots.htm

Can you find one that you like better? Please share the site with the rest of us.

1 comment:

JessieZ said...

http://mathbits.com/MathBits/TISection/Statistics1/BoxWhisker.htm

this one seemed to work pretty well for me. :)