Note: Please understand the tutorial of quartile before moving to this topic.
Table of Contents
What is box plot and how to draw the box plot for even and odd length data set?
- Box plot is a plotting of data in such a way that it is like a box shape and it represents the five number summary. Five summary is a minimum value, Quartile 1, Median, Quartile 3 and maximum value.
- End of the box is represented by inter-quartile range (IQR).
- IQR = Q3 – Q1
- The median is marked by a line within the box
- A rectangle is drawn to represent the second and third quartiles, usually with a vertical line inside to indicate the median value. The lower and upper quartiles are shown as horizontal lines either side of the rectangle. Maximum and minimum values are on the whiskers. Whiskers are the lines drawn on maximum and minimum value.
Draw the box plot for the odd length data set?
|Data = 2, 4, 5, 5, 8, 8, 9|
First of all, find the quartiles.
Q1: 4 – Lower quartile
Q2: 5 – Middle quartile
Q3: 8 – Upper quartile
Inter Quartile Range= Q3 – Q1
= 8 – 4 = 4
Population size is the total number of values in data.
Draw the box plot for the even length data set?
|Data = 8, 5, 2, 4, 8, 9, 5,7|
First of all arrange the values in sequence.
|2, 4, ♦ 5, 5, ♦ 7, 8 ♦ 8, 9|
Q1: 4 + 5 / 2 = 4.5 – Lower quartile
Q2: 5+ 7 / 2 = 6 – Middle quartile
Q3: 8 + 8 / 2 = 8 – Upper quartile