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Chapter 3: Q.25 (page 162)

What affects correlation? Make a scatterplot of the following data:

The correlation for these data is 0.5. What is responsible for reducing the correlation to this value despite a strong straight-line relationship between xand yin most of the observations?

Short Answer

Expert verified

The linear correlation coefficient is heavily influenced by the outlier (10,1).

Step by step solution

01

Given Information 

The correlation is0.5.

02

Explanation

The horizontal axis contains the x-values, while the vertical axis contains the y-values.

03

Explanation

The correlation is 0.5, which indicates that there is a modest association.

We can see that if we omit the point in the graph's bottom right corner, we get a very strong linear pattern, and the correlation coefficient would be much greater than 0.5.

Thus the outlier (10,1)strongly influences the linear correlation coefficient.

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