Question 4: Lulu Hypemarket has a record showing data on sales per year (in thousands of rials) and advertisement (in hundreds of rials) for the last five years. The record gives the following details. EX = 132 EX? = 3,502 EY = 96 EY2 = 1,870 EXY=2,553 a. Please develop the least squares estimated regression line. b. Using your regression line developed in Part a, predict the sales when advertisement is $3,000. c. At a = 0.05, determine if advertisement and sales are related (perform at test). d. Develop a 95% confidence interval for estimating the mean sale for those years when advertisement was $3,000. e. Compute the coefficient of determination.

Question 4: Lulu Hypemarket has a record showing data on sales per year (in thousands of rials) and advertisement (in hundreds of rials) for the last five years. The record gives the following details. EX = 132 EX? = 3,502 EY = 96 EY2 = 1,870 EXY=2,553 a. Please develop the least squares estimated regression line. b. Using your regression line developed in Part a, predict the sales when advertisement is $3,000. c. At a = 0.05, determine if advertisement and sales are related (perform at test). d. Develop a 95% confidence interval for estimating the mean sale for those years when advertisement was $3,000. e. Compute the coefficient of determination.

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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