Fundamentals Of Programming In SAS: A Case Studies Approach

The correct bibliographic citation for this manual is as follows: Blum, James and Jonathan Duggins. 2019. Fundamentals ofProgramming in SAS : A Case Studies Approach. Cary, NC: SAS Institute Inc.Fundamentals of Programming in SAS : A Case Studies ApproachCopyright 2019, SAS Institute Inc., Cary, NC, USA978-1-64295-228-5 (Hardcover)978-1-63526-672-6 (Paperback)978-1-63526-671-9 (Web PDF)978-1-63526-669-6 (epub)978-1-63526-670-2 (kindle)All Rights Reserved. Produced in the United States of America.For a hard-copy book: No part of this publication may be reproduced, stored in a retrieval system, or transmitted, in any form or byany means, electronic, mechanical, photocopying, or otherwise, without the prior written permission of the publisher, SAS InstituteInc.For a web download or e-book: Your use of this publication shall be governed by the terms established by the vendor at the time youacquire this publication.The scanning, uploading, and distribution of this book via the Internet or any other means without the permission of the publisher isillegal and punishable by law. Please purchase only authorized electronic editions and do not participate in or encourage electronicpiracy of copyrighted materials. Your support of others’ rights is appreciated.U.S. Government License Rights; Restricted Rights: The Software and its documentation is commercial computer softwaredeveloped at private expense and is provided with RESTRICTED RIGHTS to the United States Government. Use, duplication, ordisclosure of the Software by the United States Government is subjectto the license terms of this Agreement pursuant to, as applicable, FAR 12.212, DFAR 227.7202-1(a), DFAR 227.7202-3(a), andDFAR 227.7202-4, and, to the extent required under U.S. federal law, the minimum restricted rights as set out in FAR 52.227-19(DEC 2007). If FAR 52.227-19 is applicable, this provision serves as notice under clause (c) thereof and no other notice is required tobe affixed to the Software or documentation. The Government’s rights in Software and documentation shall be only those set forth inthis Agreement.SAS Institute Inc., SAS Campus Drive, Cary, NC 27513-2414July 2019SAS and all other SAS Institute Inc. product or service names are registered trademarks or trademarks of SAS Institute Inc. in theUSA and other countries. indicates USA registration.Other brand and product names are trademarks of their respective companies.SAS software may be provided with certain third-party software, including but not limited to open-source software, which is licensedunder its applicable third-party software license agreement. For license information about third-party software distributed with SASsoftware, refer to http://support.sas.com/thirdpartylicenses.

ContentsForeword . viiAbout This Book . ixAbout These Authors . xiAcknowledgments . xiiiChapter 1: Introduction to SAS . 11.1 Introduction. 11.2 Learning Objectives . 11.3 SAS Environments . 21.4 SAS Fundamentals. 71.5 Output Delivery System . 181.6 SAS Language Basics . 251.7 Chapter Notes . 261.8 Exercises . 30Chapter 2: Foundations for Analyzing Data and Reading Data from Other Sources . 332.1 Learning Objectives . 332.2 Case Study Activity. 342.3 Getting Started with Data Exploration in SAS. 372.4 Using the MEANS Procedure for Quantitative Summaries . 432.5 User-Defined Formats . 482.6 Subsetting with the WHERE Statement. 532.7 Using the FREQ Procedure for Categorical Summaries. 562.8 Reading Raw Data . 622.9 Details of the DATA Step Process . 702.10 Validation. 782.11 Wrap-Up Activity . 822.12 Chapter Notes . 822.13 Exercises . 85Chapter 3: Bar Chart Basics, Data Diagnostics and Cleaning, and More on Reading Datafrom Other Sources . 933.1 Learning Objectives . 933.2 Case Study Activity. 943.3 Bar Charts . 963.4 Options and Statements to Style Bar Charts . 1023.5 Creating and Using Output Data Sets from MEANS and FREQ . 1063.6 Reading Raw Data with Informats . 1113.7 Handling Incomplete Records . 1183.8 Reading and Writing Raw Data with the IMPORT and EXPORT Procedures . 1233.9 Simple Data Inspection and Cleaning . 1273.10 Wrap-Up Activity . 1353.11 Chapter Notes . 1363.12 Exercises . 137

iv ContentsChapter 4: Combining Data Vertically in the DATA Step . 1474.1 Learning Objectives.1474.2 Case Study Activity .1484.3 Vertically Combining SAS Data Sets in the DATA Step .1504.4 Managing Data Sets During Combination .1564.5 Creating Variables Conditionally .1704.6 Working with Dates and Times .1774.7 Data Exploration with the UNIVARIATE Procedure.1804.8 Data Distribution Plots .1854.9 Wrap-Up Activity.1934.10 Chapter Notes .1944.11 Exercises .194Chapter 5: Joining Data Sets on Common Values and Measuring Association . 2015.1 Learning Objectives.2015.2 Case Study Activity .2015.3 Horizontally Combining SAS Data Sets in the DATA Step .2045.4 Match-Merge Details .2145.5 Controlling Output .2205.6 Procedures for Investigating Association .2235.7 Restructuring Data with the TRANSPOSE Procedure.2335.8 Wrap-Up Activity.2405.9 Chapter Notes .2415.10 Exercises .242Chapter 6: Restructuring Data and Introduction to Advanced Reporting . 2556.1 Learning Objectives.2556.2 Case Study Activity .2556.3 DO Loops .2586.4 Arrays .2646.5 Interchanging Row and Column Information with Arrays.2696.6 Generating Tables with PROC REPORT .2746.7 Wrap-Up Activity.2876.8 Chapter Notes .2876.9 Exercises .290Chapter 7: Advanced DATA Step Concepts . 2997.1 Learning Objectives.2997.2 Case-Study Activity .2997.3 Reading Complex Raw Data Structures .3017.4 Working Across Records in the DATA Step .3117.5 Customizations in the REPORT Procedure .3207.6 Connecting to Spreadsheets and Relational Databases .3417.7 Wrap-Up Activity.3447.8 Chapter Notes .3457.9 Exercises .347

Contents vChapter 8: Clinical Trial Case Study . 3578.1 Scenario, Learning Objectives, and Introductory Activities . 3578.2 Reading and Summarizing Visit and Lab Data . 3628.3 Improving Reading of Data; Creating Charts . 3648.4 Working with Data Stacked Across Visits (and Sites) . 3668.5 Assembling and Summarizing Data—Sites 1, 2, and 3 . 3698.6 Data Restructuring and Report Writing . 3758.7 Advanced Data Reading and Report Writing—Connecting to Spreadsheets and Databases . 3768.8 Comprehensive Activity . 379Index . 381

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ForewordTo ReadersThis book is designed to help you develop an understanding of the SAS programming language and to helpyou develop good programming practices. It is intended as a learning guide and a skill builder, not as areference book. To that end, it introduces sets of topics within each chapter that are connected through asingle case study. Concepts are introduced on an as-needed basis to complete required tasks, so you areimmediately exposed to writing complete programs. As further concepts are introduced they might be newtopics, or they might revisit previously introduced topics at a more complex level. This reflects how many ofthe best SAS programmers have built their talents—by continually adding layers of knowledge onto a base setof skills. The book mimics this type of experience by increasing the complexity of the case study, requiring theaddition of newer skills, or more complex versions of earlier skills, as they are needed.Because of this circling back to content from previous chapters, a pedagogical concept known as a spiralcurriculum, you will not learn everything this book covers on a topic in any single chapter. Of course, no onebook could serve the purpose of giving a complete treatment of all concepts included; therefore, you willoften be referred to outside resources, such as SAS Documentation, for a full description of syntax or for moredetailed commentary. SAS Documentation is the standardized name used in this text for the collection of helpfiles and examples provided by SAS. This documentation is available via the Help menu in SAS or online.Reading such references is a strategy commonly used by the best SAS programmers to refine their abilitiesand is an important habit for you to develop to build your skills as a SAS programmer and to expand on thoseskills in the future.Due to the introduction of concepts in spiral fashion, it is important to begin with the setup material inChapter 1 and then to proceed through the book sequentially. For easy reference, the numbering on alloutput in Chapters 1 through 7 directly corresponds to the number of the program that generates it.However, not all programs generate output. In all chapters, the programs, output, tables, and figures arenumbered sequentially within each section. The same case study is used to provide continuity through thenarrative when building on earlier concepts. Other case studies are also available for use to build continuityfor additional programming activities and exercises. This includes a case study located in Chapter 8 for whichthe sections are aligned with the learning objectives of each chapter. Additional case studies are availableonline by visiting the author page for either author.To Classroom InstructorsAs stated in the previous section, this book is designed to tap into some of the best practices in educationaltheory as it spirals back onto topics throughout your course. It is designed by instructors with over 25 years ofcombined experience in teaching SAS either in the classroom or in industry. The more technical details areisolated in their own sections so that you can easily include or exclude them to fit the needs of your course.Multiple case studies are also provided so that the case study assignments can be customized for yourstudents’ interests and to the content presented in your course. The case study provided in Chapter 8 ensuresstudents have immediate access to a case study for reference while reading the text. Additional case studiesare made available through the author pages for either author to ensure you get the benefit of updatedmaterials on a regular basis. Any instructional materials will also be available either via the author pages (forpublic resources) or by contacting SAS to verify your status as an instructor (for instructor-only materials).These resources will be regularly updated.

viii Fundamentals of Programming in SAS: A Case Studies ApproachAbout the IPUMS CPS DataThe IPUMS CPS data includes the Integrated Public Use Microdata Series (IPUMS) and Current PopulationSurvey (CPS) beginning in 1962. These data sets provide person- and household-level information about avariety of demographic variables. A cross-section of recent data (2001, 2005, 2010, and 2015) was releasedfor this publication and is included here as the main case study in the narrative. Visit https://cps.ipums.org tolearn more about the IPUMS CPS or to extract newer data to continue honing your SAS programming skills.