A box-and-whisker plot shows the distribution of a data set using the median, quartiles, and minimum and maximum values. It was introduced by John Tukey in 1969. To construct one, the data is arranged, the median and quartiles are found by splitting the data into two halves, and these values are plotted on a number line to display the spread and central tendency of the data.
Circulatory Shock, types and stages, compensatory mechanisms
Box and whisker plots
1. BOX AND WHISKER PLOTS
Presented by-
Dr Garima Gupta
Post Graduate Resident
University College of Medical Sciences and GTB Hospital
2. INTRODUCTION
• A Box-and-Whisker Plot shows the distribution of a set of data along a
number line, dividing the data into four parts using the median and
quartiles.
• It was introduced by John Tukey in 1969, Hence also known as Tukey
Boxplot.
• It is also called as Five number summary box, as it consists of the
median, the quartiles (lower quartile and upper quartile), and the
smallest and greatest values in the distribution.
3. How to construct a Box And Whisker Plot
• For instance we have a data set of 15 values for HDL-Cholesterol
31, 41, 44, 46, 47, 48, 49, 52, 53, 54, 57, 58, 60, 62, 65 (arranged in
ascending order)
Find the median of data
31, 41, 44, 46, 47, 48, 49, 52, 53, 54, 57, 58, 60, 62, 65
Median = Q2
4. Find the medians of the two halves
31, 41, 44, 46, 47, 48, 49, 52, 53, 54, 57, 58, 60, 62, 65
Lower Median / Q1 Upper Median / Q3
5. Draw a number line that extends far enough in both directions to
include all the numbers in your data . (Vertically)
