A student uses the given set of data to compute a least-squares regression line and a correlation coefficient: 0.7 0.8 1.7 1.7 1.3 2.6 8.0 y 1 2 1 1 5 The student claims that the regression line does an excellent job of explaining the relationship between the explanatory variable x and the response variable y. Is the student correct? No, because the outlier is inflating the correlation coefficient. No, because the slope of the regression line is only 0.54. Yes, because r2 = 0.74 means that 74% of the variation in y is explained by the least-squares regression of y on x. Yes, because the correlation coefficient is r = 0.86, which is close to 1. 2.

A student uses the given set of data to compute a least-squares regression line and a correlation coefficient: 0.7 0.8 1.7 1.7 1.3 2.6 8.0 y 1 2 1 1 5 The student claims that the regression line does an excellent job of explaining the relationship between the explanatory variable x and the response variable y. Is the student correct? No, because the outlier is inflating the correlation coefficient. No, because the slope of the regression line is only 0.54. Yes, because r2 = 0.74 means that 74% of the variation in y is explained by the least-squares regression of y on x. Yes, because the correlation coefficient is r = 0.86, which is close to 1. 2.

Linear Algebra: A Modern Introduction

4th Edition

ISBN:9781285463247

Author:David Poole

Publisher:David Poole

Chapter7: Distance And Approximation

Section7.3: Least Squares Approximation

Problem 31EQ

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