Box and whisker plots (Boxplot)

Box and whisker plots (Boxplot):

Represents the variable of interest on horizontal axis

A box is drawn such a way that left end of box align with Q₁, and the right end align with Q₃.

Divide the box into two parts by a vertical line that aligns with the median Q₂

Draw a horizontal line called a whisker from the left end of the box to the point that align with the smallest measurement of the data set

Draw another horizontal line or whisker from the right end of the box to the point that align with the largest measurement of the data set

Outliers: it is an observation whose value, “x”, either exceeds the value of the third quartile by a magnitude greater than 1.5(IQR) or is less than the value of first quartile by a magnitude greater than 1.5(IQR).

That is

{Q₁- 1.5(IQR)} > x > {Q₃ + 1.5(IQR)}

PSM / COMMUNITY MEDICINE by Dr Abhishek Jaiswal is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License.
Based on a work at learnpsm@blogspot.com.
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