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Chapter 12: Q. 8 (page 797)

A residual plot from the least-squares regression is shown below. Which of the following statements is supported by the graph

(a) The residual plot contains dramatic evidence that the standard deviation of the response about the population regression line increases as the average number of putts per round increases.

(b) The sum of the residuals is not 0. Obviously, there is a major error present.

(c) Using the regression line to predict a player’s total winnings from his average number of putts almost always results in errors of less than \(200,000.

(d) For two players, the regression line under predicts their total winnings by more than\)800,000.

(e) The residual plot reveals a strong positive correlation between average putts per round and prediction errors from the least-squares line for these players.

Short Answer

Expert verified

For two players, the regression Line under predicts their total winnings by more than$800,000. The correct option is (d).

Step by step solution

01

Given Information 

02

Explanation

(A) The vertical distribution between points in the residual plot does not tend to adjust with the horizontal axis differential values, thus it is not helped.

(B) This cannot be determined from a residual map since the sum of the residuals can be zero.

(C) Not recommended because residuals in excess of $200,000are available.

(D) Assist, because the residual plot shows two locations on the vertical axis with values greater than $800,000.

(E) A residual plot correlation's direction (positive or negative) cannot be calculated if it is unsupported.

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Most popular questions from this chapter

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