Copyright © 2012 Pearson Education, Inc. All rights reserved. Chapter 4 Multiple Regression Models.

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Transcript of Copyright © 2012 Pearson Education, Inc. All rights reserved. Chapter 4 Multiple Regression Models.

Copyright © 2012 Pearson Education, Inc. All rights reserved.

Chapter 4

Multiple Regression Models

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Section 4.1

General

Form of a Multiple Regression Model

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Section 4.2

Model Assumptions

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Section 4.3

A First-Order Model with Quantitative Predictors

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Figure 4.1 Graphs of E(y) = 1+ 2x1 = x2 for x2 = 0,1,2

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Section 4.4

Fitting the Model: The Method of Least Squares

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Figure 4.2 MINITAB side-by-side scatterplots for the data of Table 4.1

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Figure 4.3 SAS regression output for the auction price model, Example 4.1

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Section 4.5

Estimation of 2, the Variance of

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Section 4.6

Testing the Utility of a Model:

The Analysis of Variance

F-Test

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Figure 4.4 Rejection region for the global F-test

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Figure 4.5 MINITAB regression printout for grandfather clock model

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Section 4.7

Inferences About the Individual Parameters

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Figure 4.6 SAS regression output for the auction price model, Example 4.4

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Multiple Coefficients of Determination:

R2 and R2

Section 4.8

a

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Figure 4.7 A portion of the SPSS regression output for the auction price model

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Section 4.9

Using the Model for Estimation and Prediction

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Figure 4.8 MINITAB printout with 95% confidence intervals for grandfather clock model

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Section 4.10

An Interaction Model with Quantitative Predictors

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Figure 4.9 Graphs of 1 + 2x1 – x2 + x1x2 for x2 = 0,1,2

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Figure 4.10 Examples of no-interaction and interaction models

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Figure 4.11 MINITAB regression printout for grandfather clock model with interaction

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Section 4.11

A Quadratic (Second-Order)

Model with a Quantitative Predictor

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Figure 4.12 Graphs for two quadratic models

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Figure 4.13 SPSS scatterplot for data of Example 4.7

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Figure 4.14 SPSS output for quadratic model of Example 4.7

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Figure 4.15 MINITAB graph of least squares fit for the quadratic model

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Figure 4.16 Potential misuse of quadratic model

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Section 4.12

More Complex Multiple Regression Models (Optional)

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Figure 4.17 Graph of E(y) = 1 + 7x1 - 10x2 + 5x1x2 – + 32

1x22x

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Figure 4.18 SAS multiple regression output for Example 4.8

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Figure 4.19 MINITAB multiple regression output for Example 4.9

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Figure 4.20 MINITAB multiple regression output for Example 4.10

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Section 4.13

A Test for Comparing Nested Models

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Figure 4.21 Rejection region for the F-test Ho: 4 = 5 = 0

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Figure 4.22 SAS output for complete model, Example 4.11

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Figure 4.23 SAS output for reduced model, Example 4.11

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Section 4.14

A Complete Example

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Figure 4.24 SAS output for complete second-order model for road cost

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Figure 4.25 SAS output for reduced model for road cost

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Figure 4.26 Plot of the least squares lines for the reduced model

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Figure 4.27 SAS output showing prediction intervals for reduced model