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Chapter 8: Q5CRE (page 356)

Lightning Deaths The accompanying bar chart shows the numbers of lightning strike deaths broken down by gender for a recent period of nine years. What is wrong with the graph?

Short Answer

Expert verified

The vertical scale on the graph does not begin from 0. The difference between the number of males and females is falsely enlarged. It makes the reader believe that the number of male deaths is more than 20 times the number of female deaths when the actual proportion of male to female deaths is approximately 4:1.

Step by step solution

01

Given information

A bar chart is plotted showing the number of deaths that have occurred due to lightning strikes based on gender.

02

Error in the graph

A bar chart is used to depict the frequency corresponding to each category under consideration. The length of the bars denotes the frequency.

To accurately represent the given frequency, the vertical axis denoting the frequency should begin from 0.

Here, the vertical axis does not begin with a 0.

This results in a false illusion that there are significantly more males who die due to lightning than females by exaggerating the difference between the two frequencies.

In reality, the number of males is approximately 4-5 times the number of females. Here, the graph falsely depicts that males are more than 20 times the number of females.

Therefore, the given graph deceives the reader.

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