Box Plot

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http://weatherstories.ssec.wisc.edu/stories/armistice_day/climate.html

A box plot is graphical way of depicting groups of numerical data through their group quartiles with basic statistical concepts like mean, median range and mode. A box plot may have lines extending vertically from the boxes, the "whiskers" which indicates variability outside the upper and lower quartiles. Box plots display variation in samples of a statistical population without having any assumptions of the statistical distribution. The spacing between the different parts of the box indicate the degree of dispersion and degree of skew in the data, while also showing outliers. Box plots can be drawn either horizontally or vertically. The image above is an example of a box plot of daily mean temperature in Fahrenheit for November 1940, Madison, Wisconsin.