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Box-and-Whisker Plot


A Histogram-like method of displaying data invented by J. Tukey (1977). Draw a box with ends at the Quartiles $Q_1$ and $Q_3$. Draw the Median as a horizontal line in the box. Extend the ``whiskers'' to the farthest points. For every point that is more than 3/2 times the Interquartile Range from the end of a box, draw a dot on the corresponding top or bottom of the whisker. If two dots have the same value, draw them side by side.


Tukey, J. W. Explanatory Data Analysis. Reading, MA: Addison-Wesley, pp. 39-41, 1977.

© 1996-9 Eric W. Weisstein