A scatterplot and a least-squares regression line are shown in the figure. What effect does point P have on the slope of the regression line and the correlation?

a. Point P increases the slope and increases the correlation.

b. Point P increases the slope and decreases the correlation.

c. Point P decreases the slope and decreases the correlation.

d. Point P decreases the slope and increases the correlation .

e. No conclusion can be drawn because the other coordinates are unknown.

Short Answer

Expert verified

The correct option is - (e) Point P decreases the slope and increases the correlation.

Step by step solution

01

Given Information 

We are given a scatterplot and a point P . We need to find about the slope and correlation .

02

Explanation 

The point P pulls linear squared regression line upwards . The slope decreases whereas correlation tends to increase . Also a positive correlation exists when one variable tends to decrease as the other variable decreases, or one variable tends to increase when the other increases. Hence point P decreases the slope and increases the correlation .

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