by Xiao Chen, Phil Ender, Michael Mitchell and Christine Wells (in alphabetical order)

The aim of these materials is to help you increase your skills in using regression analysis with SAS. This web book does not teach regression, per se, but focuses on how to perform regression analyses using SAS. It is assumed that you have had at least a one quarter/semester course in regression (linear models) or a general statistical methods course that covers simple and multiple regression and have access to a regression textbook that explains the theoretical background of the materials covered in these chapters. These materials also assume you are familiar with using SAS, for example that you have taken the Introduction to SAS class or have equivalent knowledge of SAS. If you are a member of the UCLA community and have questions about these materials, we welcome you to send questions via email to or to visit our consulting services .

## Book Chapters

(also see short outline)

- Section 1: Regression Concepts
- Section 2: Categorical
Coding and Interactions in Depth
- Chapter 5 – Additional coding systems for categorical variables in regression analysis
- Chapter 6 – More on interactions of categorical variables in regression analysis (under development)
- Chapter 7 – More on interactions of continuous and categorical variables in regression analysis (under development)
- Chapter 8 – Interactions of continuous variables in regression analysis (under development)

## Accessing the Data Files

All data files used in the book are available as SAS version 8 (.sas7bdat) files. The are listed below in alphabetical order and can be downloaded by clicking on them.

- acadindx.sas7bdat
- bbwt.sas7bdat
- crime.sas7bdat
- davis.sas7bdat
- elemapi.sas7bdat
- elemapi2.sas7bdat
- hsb2
- nations.sas7bdat
- tree.sas7bdat
- wage.sas7bdat

We have also made a self extracting zip file that contains all of the above files. You can download it by clicking on /sas/webbooks/reg/sasreg.exe.

You can store these data files in any folder on your computer. Our
examples will assume that you have stored the files in a folder called ** c:sasreg**
, so whenever an example refers to ** c:sasreg** you can change that to the name of
the folder where you stored the files on your computer.

## Recommended Readings

It is important to refer to the SAS manuals to learn about using SAS. We hope these chapters will introduce you to a number of new SAS commands, however it is important to have the manuals to show you the detail of the syntax of the commands, examples, and technical explanations of what the commands are doing.

## Regression Textbooks

There may be a number of regression concepts introduced in the chapters that are new to you. Since the chapters focus on how to analyze your data using SAS (and not the underlying concepts) you may want to have a good regression book to help explain such concepts. Below we list a number of regression books that we would recommend. Each of these books is very good in their own way and yet, each one of them is different. Different individuals prefer different books from the list, and some of them may appeal to your learning style more than others. If you are interested in acquiring one of these books, we would invite you to preview them via our Statistics Books for Loan program. Also note that some of these books have corresponding web pages at our SAS Textbook Examples page.

Chatterjee, S., Hadi, A., & Price, B. (2000) *Regression analysis by example.*
New York: Wiley. ISBN 0-471-31946-5

Fox, J. (1997) *Applied regression analysis, linear models, and related methods.*
Thousand Oaks, CA: Sage Publications. ISBN 0-8039-4540-X

Hamilton, L.C. (1992) *Regression with graphics.* Belmont, CA: Wadsworth. ISBN
0-534-15900-1

Pedhazur, E.J. (1997). *Multiple regression in behavioral research, third edition.*
New York: Harcourt Brace College Publishers. ISBN 0-03-072831-2

## Recommended Web Pages on Regression

See the For More Information page for additional readings and resources on regression analysis in SAS.

## How to Cite This Page

We welcome you to cite our web book as you would cite other books or journal articles. Here is the recommended method for citing this book.

Chen, X., Ender, P., Mitchell, M. and Wells, C. (2003).
*Regression with SAS*, from
http://www.ats.ucla.edu/stat/sas/webbooks/reg/default.htm .