Quick Start to Data Analysis with SAS Table of Contents. Chapter 1 Introduction 1. Chapter 2 SAS Programming Concepts 7

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1 Chapter 1 Introduction 1 SAS: The Complete Research Tool 1 Objectives 2 A Note About Syntax and Examples 2 Syntax 2 Examples 3 Organization 4 Chapter by Chapter 4 What This Book Is Not 5 Chapter 2 SAS Programming Concepts 7 Fundamentals 7 Datasets 7 Units of Work 8 Syntax 9 Defaults 10 Running the Program 10 An Annotated Example 12 Recap 15 Chapter 3 Preparing the Data for Analysis 17 Understanding the Input Data 18 Missing Data 19 Naming the Dataset: The DATA Statement 19 Locating the Data: The INFILE, CARDS, and DATALINE Statements 20 Describing the Data Layout: The INPUT Statement 21 List Input 21 Column Input 22 Formatted Input 23 INPUT Statement Formats 23 Mixing Input Styles 24 Which Style to Use? 25 Common Problems 25 Permanent Versus Temporary SAS Datasets 26 What's in the Dataset? 26 Linking to the System: The LIBNAME Statement 27 "Two-Level" Dataset Names 28 Recap 28 Syntax Summary 28 Content Review 29 Chapter 4 Introduction to DATA Step Programming 31 Documenting Your Work: Using Comments 32 Reading SAS Datasets: SET 33 Syntax 33 Examples 34 Performing Calculations: Assignment Statements 35 Syntax and Usage Notes 35 Examples 36 Building Logical Expressions 37 Comparison Operators 37 Logical Operators 38

2 Examples 39 Conditional Execution: IF-THEN -ELSE 39 Forms of IF-THEN-ELSE 40 Examples 40 A Note About Receding 41 Selecting Observations: OUTPUT 42 Increasing Variable Description: LABEL 43 Controlling Display of the Data: FORMAT 43 Recap 45 Syntax Summary 45 Content Review 46 Chapter 5 Combining Datasets 47 Methods 48 Concatenation 48 Interleaving 48 Matched Merge 48 Terminology 48 Dataset Options 50 Concatenation 50 Examples 51 Interleaving 53 Example 53 Matched Merge 54 Syntax and Usage 54 Examples 56 Recap 59 Syntax Summary 59 Content Review 59 Chapter 6 Introduction to Procedures 61 Statements Used with Most Procedures 62 Clarifying Content: TITLE and FOOTNOTE 62 Processing Data in Groups: BY 63 Controlling Appearance: FORMAT and LABEL Revisited 63 Selecting Observations: WHERE 64 Identifying Groups of Variables: Variable Lists 65 Displaying the Dataset: PRINT 66 Example 66 Identifying the Dataset 67 Identifying and Ordering Variables 68 Requesting Counts and Sums 69 Aesthetics 69 Example 70 Rearranging the Dataset: SORT 72 Specifying the Datasets 72 Specifying Observation Order: The BY Statement 72 Sorting Options 73 Getting Information about the Dataset: CONTENTS 74 Identifying the Datasets 74 Controlling the Amount of Output 74 Example 74 Recap 75 Syntax Summary 75 Content Review 76

3 Chapter 7 A Statistical Roadmap for the SAS System 77 What's in a PROC Name? 77 A Warning 78 The Roadmap 78 Univariate Statistics 78 Simple Bivariate Tests and Measures of Association 79 Comparing Means and Analysis of Variance 79 Estimating Prediction Equations with Regression 80 Specialised Regression Models 81 Models for More than One Dependent Variable: Multivariate Statistics 81 Measurement and Scaling Techniques 82 Grouping and Predicting Group Membership 83 Navigating the Documentation Maze 83 Documentation 84 Recap 85 Chapter 8 Statistics for Single Variables 87 Examining Distributions of Categorical Variables 87 Creating Frequency Distributions 87 Visualizing Frequency Distributions with Bar Charts 91 Examining Distributions of Continuous Variables 98 PROC MEANS: Basic Summary Statistics for Continuous Variables 102 Basic MEANS Syntax 102 Display and Analytical Options 102 Specifying Analysis Variables 103 PROC UNIVARIATE: Obtaining Detailed Statistics, Tables, and Graphs 104 Basic UNIVARIATE Syntax 104 Display and Analytical Options 107 Recap 109 Syntax Summary 109 Content Review 110 Chapter 9 Statistics for Relationships with Continuous Dependent Variables 111 ANOVA Statistics for Categorical Independent Variables 112 Visualizing Group Distributions with PROC CHART 112 Visualizing Distributions with PROC UN IV API A TE 115 Testing Differences in Means for Two Independent Groups: PROCTTEST 116 Testing Differences in Means for Several Independent Groups: PROCGLM 118 Specifying Post Hoc Comparisons 121 Using PROC GLMfor Two-Way to N-Way ANOVAs 124 Testing for Differences of Related Means 128 Regression: Statistics for Continuous Independent and Dependent Variables 12 Visualizing Bivariate Relationships Using PROC PLOT 133 Estimating Regression Models with PROC REG 136 Analysis of Covariance: Statistics for Both Categorical and Continuous Independent Variables 143 Using PROC GLMfor ANCOVA 143 Interpreting PROC GLM ANCOVA Output 147 Using PROC REG for ANCOVA 148 Recap 152 Syntax Summ ary 152 Content Review 153 References 154 Chapter 10 Statistics for Relationships with Categorical Dependent Variables 155

4 Examining Bivariate Relationships 156 Producing a Crosstabulation with Tests and Measures of Association 156 Entering Previously Crosstabulated Data 162 Testing for Differences Between Groups on a Rank-Ordered Dependent Variable 164 Logistic Regression: Estimating a Prediction Equation for a Dichotomous Dependent Variable 167 PROC LOGISTIC: Estimating Logistic Regression Models with Continuous Independent Variables 168 PROC CATMOD: Estimating Logistic Regression Models with Categorical Independent Variables 174 Recap 179 Syntax Summary 179 Content Review 180 References 180 Chapter 11 More About SAS Programming 183 Options 184 Identifying System Settings 184 Frequently Used Options 185 DATA Step Programming Revisited 187 Grouping Related Statements: DO and END 187 Streamlining Calculations: Functions 187 Working with Dates 189 Background 190 Assigning Date Values 190 Manipulating Date Values 191 Displaying Date Values 192 Recap 193 Syntax Summary 193 Content Review 194 Chapter 12 PROCs That Create Datasets 195 Aggregating by Groups: The MEANS Procedure 195 The PROC MEANS Statement 196 Instructions for Aggregation: The CLASS Statement 197 Specifying Analysis Variables: The VAR Statement 197 Naming and Requesting Statistics: The OUTPUT Statement 198 Examples 200 Standardization of Data: The STANDARD Procedure 202 The PROC STANDARD Statement 202 Specifying Analysis Variables: The VAR Statement 203 Examples 203 Rank-Ordering Data: The RANK Procedure 204 Background 204 The PROC RANK Statement 204 Specifying Input and Output Variables: The VAR and RANK Statements 20\ Examples 206 Recap 207 Syntax Summary 207 Content Review 208 Chapter 13 Receding and Labeling with PROC FORMAT 209 Concepts 210 Syntax 210 Using Formats for Display 212 Analytical Use of Formats 214 Using Formats in DATA Steps 217

5 Recap 218 Syntax Summary 218 Content Review 218 Chapter 14 Working with Character Data 221 Principles 221 Length 221 Magnitude 221 Specifying Length: The LENGTH Statement 222 Character-Handling Operators 223 The Concatenation Operator 223 The Colon (:) Comparison Modifier 224 Character-Handling Functions 224 Obtaining Variable Information: LENGTH 225 Extracting Part of a String: SUBSTR 225 Locating Strings Within a String: INDEX Variants and VERIFY 226 Altering the Appearance of a String 227 Recap 229 Syntax Summary 229 Content Review 229 Chapter 15 Putting It All Together 231 Predicting Opinion About Taxes 231 Predicting Employee Turnover 242 Treating Fear of Snakes 255 Recap 259 Closing Comment 259 References 260 Appendix A Using the Display Manager 261 Display Manager Background 261 Syntax 265 A Sample Display Manager Session 266 Entering the Program 266 Running the Program 267 Moving Through the Output 268 Revising the Program 268 Saving Your Work 269 Leaving SAS 270 Retrieving Your Work 270 Customizing Your Environment with the KEYS Window 271 Syntax Summary 272 Command Line Commands 272 Line Commands 274 Appendix B Resources 277 Person-to-Person 277 Help Desks 277 "Power Users" 278 User Groups 278 Courses 278 Electronic Resources 279 Online Help 279 SAS/Assist 279 SAS Sample Library 279

6 The SAS-L List Server 280 World Wide Web 280 Hard Copy 281 Local Documentation 281 SAS Institute Publications 281 Books by Users 281 Appendix C Common Problems (and Solutions) 283 Divison by Zero 283 Unbalanced Quotes 284 DOing Without ENDing 285 Uninitialized Variables 286 Subtle Omissions of Periods 287 Display Manager "Stalls" 287 Data Type Conversion Messages 288 New Character Variables Appear Truncated 289 Subsetting into 0 Observations 289 Complaints About Correct Syntax 290 Unbalanced Parentheses 291 "Dataset Not Found" Messages 292 Every Calculated Value Is Missing 292 Conflicting Data Types 293 All Calculations Are Missing 294 Index 295