n the accompanying table, x is the tensile force applied to a steel specimen in thousands of pounds, and y is the resulting elongation in thousands of an inch: X 1 2 3 4 5 Y 14 33 40 63 76 85 a) Find the equation of the least squares line, and use it to predict the elongation when the tensile force is 3.5 thousand pounds. b) Construct a 95% confidence interval for B, the elongation per thousand pounds of tensile stress; c) Find 95% limits of prediction for the elongation of a specimen with x 3.5 thousand pounds.

n the accompanying table, x is the tensile force applied to a steel specimen in thousands of pounds, and y is the resulting elongation in thousands of an inch: X 1 2 3 4 5 Y 14 33 40 63 76 85 a) Find the equation of the least squares line, and use it to predict the elongation when the tensile force is 3.5 thousand pounds. b) Construct a 95% confidence interval for B, the elongation per thousand pounds of tensile stress; c) Find 95% limits of prediction for the elongation of a specimen with x 3.5 thousand pounds.

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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