In a study of copper bars, the relationship between shear stress in ksi (x) and shear strain in % (y) was summarized by the least-squares line y = −20.00 + 2.56x. There were a total of n = 18 observations, and the coefficient of determination was r 2 = 0.9111. If the total sum of squares was ∑ni=1(yi−y⎯⎯)2∑i=1n(yi−y¯)2 = 234.19, compute the estimated error variance s2. Round the answer to three decimal places.

In a study of copper bars, the relationship between shear stress in ksi (x) and shear strain in % (y) was summarized by the least-squares line y = −20.00 + 2.56x. There were a total of n = 18 observations, and the coefficient of determination was r 2 = 0.9111. If the total sum of squares was ∑ni=1(yi−y⎯⎯)2∑i=1n(yi−y¯)2 = 234.19, compute the estimated error variance s2. Round the answer to three decimal places.

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 34EQ

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