Modeling Nonlinearity and Interaction in Regression Analysis Using Spline Variables

Roger A. Wojtkiewicz

• Publisher: SAGE Publications, Inc
• Year: 2025
• Print ISBN: 9781071950340
• eBook ISBN: 9781071950364
• Edition: 1
• Topic: Social Sciences
• Subtopic: Social Science Research & Methodology
• Index: Social Sciences

"Spline variables and their interactions play a crucial role in the field of social science. This book offers a comprehensive and detailed exploration of this method, providing valuable insights and information for researchers in the field."
--Man-Kit Lei, The University of Georgia

This volume addresses the issue of linear constraints in regression modeling. Author Roger A. Wojtkiewicz uses the method of knotted spline variables (also known as piecewise linear regression) and a new method involving group spline variables to model nonlinearity in a variety of situations. Using spline variables to model nonlinearity allows researchers to specify unrestricted models for models that involve interval variables, allowing for greater flexibility in modeling any possible interaction.

Table of contents

• Cover
• Acknowledgements
• Series
• Half Title
• Dedication
• Publisher Note
• Title Page
• Copyright Page
• Brief Contents
• Detailed Contents
• Series Editor Introduction
• Acknowledgments
• About the Author
• 1 Introduction
• 2 Basics of Spline Variables
• 3 Applications of Spline Variables
• 4 Interaction Between Interval and Categorical Variables
• 5 Interaction Between Interval Variables
• 6 Concluding Remarks
• Appendix 1 — Example of Derivation of Interaction Model With Interval Variable Conditioned on Categorical Variable From Dummy Variable Model
• Appendix 2 — Example of Derivation of Interaction Model With Interval Variable Conditioned on Interval Variable From Dummy Variable Model
• References
• Index