Preface
Synopsis
Computing
To Readers, Students, and Instructors
Acknowledgments
Part I Preliminaries
Chapter 1 Statistics and Social Science
1.1 Statistical Models and Social Reality
1.2 Observation and Experiment
1.3 Populations and Samples
1.4 Summary
1.5 Recommended Reading
Chapter 2 What Is Regression Analysis?
2.1 Preliminaries
2.2 Naive Nonparametric Regression
2.3 Local Averaging
2.3.1 Weighted Local Averages*
2.4 Summary
Chapter 3 Examining Data
3.1 Univariate Displays
3.1.1 Histograms
3.1.2 Density Estimation*
3.1.3 Quantile-Comparison Plots
3.1.4 Boxplots
3.2 Plotting Bivariate Data
3.3 Plotting Multivariate Data
3.4 Summary
3.5 Recommended Reading
Chapter 4 Transforming Data
4.1 The Family of Powers and Roots
4.2 Transforming Skewness
4.3 Transforming Nonlinearity
4.4 Transforming Non-Constant Spread
4.5 Transforming Proportions
4.6 Summary
4.7 Recommended Reading
Part II: Linear Models and Least Squares
Chapter 5 Linear Least-Squares Regression
5.1 Simple Regression
5.1.1 Least-Squares Fit
5.1.2 Simple Correlation
5.2 Multiple Regression
5.2.1 Two Independent Variables
5.2.2 Several Independent Variables
5.2.3 Multiple Correlation
5.2.4 Standardized Regression Coefficients
5.3 Summary
Chapter 6 Statistical Inference for Regression
6.1 Simple Regression
6.1.1 The Simple-Regression Model
6.1.2 Properties of the Least-Squares Estimator
6.1.3 Confidence Intervals and Hypothesis Tests
6.2 Multiple Regression
6.2.1 The Multiple-Regression Model
6.2.2 Confidence Intervals and Hypothesis Tests
Individual Slope Coefficients
All Slopes
A Subset of Slopes
6.3 Empirical versus Structural Relations
6.4 Measurement Error in Independent Variables*
6.5 Summary
Chapter 7 Dummy-Variable Regression
7.1 A Dichotomous Independent Variable
7.2 Polytomous Independent Variables
7.3 Modeling Interactions
7.3.1 Constructing Interaction Regressors
7.3.2 The Principle of Marginality
7.3.3 Interactions With Polytomous Independent Variables
7.3.4 Hypothesis Tests for Main Effects and Interactions
7.4 A Caution Concerning Standardized Coefficients
7.5 Summary
Chapter 8 Analysis of Variance
8.1 One-Way Analysis of Variance
8.2 Two-Way Analysis of Variance
8.2.1 Patterns of Means in the Two-Way Classification
8.2.2 The Two-Way ANOVA Model
8.2.3 Fitting the Two-Way ANOVA Model to Data
8.2.4 Testing Hypotheses in Two-Way ANOVA
8.2.5 Equal Cell Frequencies
8.2.6 Some Cautionary Remarks
8.3 Higher-Way Analysis of Variance*
8.3.1 The Three-Way Classification
8.3.2 Higher-Order Classifications
8.3.3 Empty Cells in ANOVA
8.4 Analysis of Covariance
8.5 Linear Contrasts of Means
8.6 Summary
Chapter 9 Statistical Theory for Linear Models*
9.1 Linear Models in Matrix Form
9.1.1 Dummy Regression and Analysis of Variance
9.1.2 Linear Contrasts
9.2 Least-Squares Fit
9.3 Properties of the Least-Squares Estimator
9.3.1 The Distribution of the Least-Squares Estimator
9.3.2 The Gauss-Markov Theorem
9.3.3 Maximum-Likelihood Estimation
9.4 Statistical Inference for Linear Models
9.4.1 Inference for Individual Coefficients
9.4.2 Inference for Several Coefficients
9.4.3 General Linear Hypotheses
9.4.4 Joint Confidence Regions
9.5 Random Regressors
9.6 Specification Error
9.7 Summary
9.8 Recommended Reading
Chapter 10 The Vector Geometry of Linear Models*
10.1 Simple Regression
10.1.1 Variables in Mean-Deviation Form
10.1.2 Degrees of Freedom
10.2 Multiple Regression
10.3 Estimating the Error Variance
10.4 Analysis-of-Variance Models
10.5 Summary
10.6 Recommended Reading
Part III: Linear-Model Diagnostics
Chapter 11 Unusual and Influential Data
11.1 Outliers, Leverage, and Influence
11.2 Assessing Leverage: Hat-Values
11.3 Detecting Outliers: Studentized Residuals
11.3.1 Testing for Outliers in Linear Models
11.3.2 Anscombe's Insurance Analogy
11.4 Measuring Influence
11.4.1 Influence on Standard Errors
11.4.2 Influence on Collinearity
11.5 Numerical Cutoffs for Diagnostic Statistics
11.5.1 Hat-Values
11.5.2 Studentized Residuals
11.5.3 Measures of Influence
11.6 Joint Influence and Partial-Regression Plots
11.7 Should Unusual Data Be Discarded?
11.8 Some Statistical Details*
11.8.1 Hat-Values and the Hat Matrix
11.8.2 The Distribution of the Least-Squares Residuals
11.8.3 Deletion Diagnostics
11.8.4 Partial-Regression Plots
11.9 Summary
11.10 Recommended Reading
Chapter 12 Nonlinearity and Other Ills
12.1 Non-Normally Distributed Errors
12.1.1 Confidence Envelopes by Simulated Sampling*
12.2 Non-Constant Error Variance
12.2.1 Residual Plots
12.2.2 Weighted-Least-Squares Estimation*
12.2.3 Correcting OLS Standard Errors for Non-Constant Variance*
12.2.4 How Non-Constant Error Variance Affects the OLS Estimator*
12.3 Nonlinearity
12.3.1 Partial-Residual Plots
12.3.2 When Do Partial-Residual Plots Work?
CERES Plots*
12.4 Discrete Data
12.4.1 Testing for Nonlinearity `Lack of Fit')
12.4.2 Testing for Non-Constant Error Variance
12.5 Maximum-Likelihood Methods*
12.5.1 Box-Cox Transformation of Y
12.5.2 Box-Tidwell Transformation of the X's
12.5.3 Non-Constant Error Variance Revisited
12.6 Structural Dimension*
12.7 Summary
12.8 Recommended Reading
Chapter 13 Collinearity
13.1 Detecting Collinearity
13.1.1 Principal Components*
Two Variables
The Data Ellipsoid
Summary
Diagnosing Collinearity
13.1.2 Generalized Variance Inflation*
13.2 Coping With Collinearity: No Quick Fix
13.2.1 Model Re-Specification
13.2.2 Variable Selection
13.2.3 Biased Estimation
Ridge Regression*
13.2.4 Prior Information About the Regression Coefficients
13.2.5 Some Comparisons
13.3 Summary
Part IV: Beyond Linear Least Squares
Chapter 14 Extending Linear Least Squares*
14.1 Time-Series Regression
14.1.1 Generalized Least-Squares Estimation
14.1.2 Serially Correlated Errors
GLS Estimation With Autoregressive Errors
Empirical GLS Estimation
14.1.3 Diagnosing Serially Correlated Errors
14.1.4 Concluding Remarks
14.2 Nonlinear Regression
14.2.1 Polynomial Regression
14.2.2 Transformable Nonlinearity
14.2.3 Nonlinear Least Squares
14.3 Robust Regression
14.3.1 M-Estimation
Estimating Location
M-Estimation in Regression
14.3.2 Bounded-Influence Regression
14.4 Nonparametric Regression
14.4.1 Smoothing Scatterplots by Lowess
Selecting the Span
Statistical Inference
14.4.2 Additive Regression Models
Fitting the Additive Regression Model
Statistical Inference
Semi-Parametric Models
14.5 Summary
Time-Series Regression
Nonlinear Regression
Robust Regression
Nonparametric Regression
14.6 Recommended Reading
Chapter 15 Logit and Probit Models
15.1 Models for Dichotomous Data
15.1.1 The Linear-Probability Model
15.1.2 Transformations of pi: Logit and Probit Models
15.1.3 An Unobserved-Variable Formulation
15.1.4 Logit and Probit Models for Multiple Regression
15.1.5 Estimating the Linear Logit Model*
15.1.6 Diagnostics for Logit Models*
Residuals in Logit model
Residual and Partial-Residual Plots
Hat-Values and the Hat-Matrix
Studentized Residuals
Influence Diagnostics
Partial-Regression Plot
Constructed-Variable Plot for Transforming an X
15.2 Models for Polytomous Data
15.2.1 The Polytomous Logit Model
Details of Estimation*
15.2.2 Nested Dichotomies
Why Nested Dichotomies are Independent*
15.2.3 Ordered Logit and Probit Models
15.2.4 Comparison of the Three Approaches
15.3 Discrete Independent Variables
15.3.1 The Binomial Logit Model*
15.4 Generalized Linear Models*
15.5 Summary
15.6 Recommended Reading
Chapter 16 Assessing Sampling Variation
16.1 Bootstrapping
16.1.1 Bootstrapping Basics
16.1.2 Bootstrap Confidence Intervals
Normal-Theory Intervals
Percentile Intervals
Improved Bootstrap Intervals*
16.1.3 Bootstrapping Regression Models
16.1.4 Bootstrap Hypothesis Tests*
16.1.5 Bootstrapping Complex Sampling Designs
16.1.6 Concluding Remarks
16.2 Cross-Validation
16.2.1 An Illustration
16.2.2 Concluding Remarks
16.3 Summary
16.4 Recommended Reading
Appendix A: Notation
Appendix B: Vector Geometry*
B.1 Basic Operations
B.2 Vector Spaces and Subspaces
B.3 Orthogonality and Orthogonal Projections
B.4 Recommended Reading
Appendix C Multivariable Differential Calculus
C.1 Partial Derivatives
C.2 Lagrange Multipliers
C.3 Matrix Calculus
Appendix D Probability and Estimation
D.1 Elementary Probability Theory
D.1.1 Basic Definitions
D.1.2 Random Variables
Vector Random Variables*
D.1.3 Transformations of Random Variables
Transformations of Vector Random Variables*
D.2 Discrete Distributions*
D.2.1 The Binomial Distribution
D.2.2 The Multinomial Distribution
D.2.3 The Poisson Distribution
D.3 Continuous Distributions
D.3.1 The Normal Distribution
D.3.2 The Chi-Square Distribution
D.3.3 The t-Distribution
D.3.4 The F-Distribution
D.3.5 The Multivariate-Normal Distribution*
D.4 Asymptotic Distribution Theory*
D.4.1 Probability Limits
D.4.2 Asymptotic Expectation and Variance
D.4.3 Asymptotic Distribution
D.5 Properties of Estimators
D.5.1 Bias
Asymptotic Bias*
D.5.2 Mean-Squared Error and Efficiency
Asymptotic Efficiency*
D.5.3 Consistency*
D.5.4 Sufficiency*
D.6 Maximum-Likelihood Estimation
Generalization of the Example*
D.6.1 Properties of Maximum-Likelihood Estimators*
D.6.2 Wald, Likelihood-Ratio, and Score Tests
An Illustration*
D.6.3 Several Parameters*
D.7 Recommended Reading