Q3: Table below shows the age in years and the retail value in thousands of pounds of a random sample of ten cars of the same make and model. 3 24.8 4. 24.6 3 3 4 6. 28.7 26.0 30.5 23.8 23.8 20.4 21.6 22.1 i. Compute the least squares regression line. Plot it on the scatter diagram. ii. Interpret the meaning of the slope of the least squares regression line in the context of the problem. iii. Suppose a four-year-old car of this make and model is selected at random. Use the regression equation to predict its retail value. iv. Suppose a 2020-year-old car of this make and model is selected at random. Use the regression equation to predict its retail value. Interpret the result. Comment on the validity of using the regression equation to predict the price of a brand new car of this make and model. v.

Q3: Table below shows the age in years and the retail value in thousands of pounds of a random sample of ten cars of the same make and model. 3 24.8 4. 24.6 3 3 4 6. 28.7 26.0 30.5 23.8 23.8 20.4 21.6 22.1 i. Compute the least squares regression line. Plot it on the scatter diagram. ii. Interpret the meaning of the slope of the least squares regression line in the context of the problem. iii. Suppose a four-year-old car of this make and model is selected at random. Use the regression equation to predict its retail value. iv. Suppose a 2020-year-old car of this make and model is selected at random. Use the regression equation to predict its retail value. Interpret the result. Comment on the validity of using the regression equation to predict the price of a brand new car of this make and model. v.

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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