Introduction to SPSS

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Introduction to SPSS

• Hsin-Hui Lin, Ph.D.
• Paul M. Montebello, Ph.D.

Policy Planning Research Division Department of
Childrens Services Tennessee State
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Contents

• 1. Getting Started
• 2. Data Management
• 3. Using the SPSS Help Function

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1. Getting Started

• 1.1 What is SPSS?
• 1.2 Features of SPSS Base Module
• 1.3 Basic Concepts

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1.1 What is SPSS?

• SPSS stands for Statistical Package for the
  Social Sciences
• Modular
• Integrated
• User-friendly

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Basic SPSS Functions

• Access Data
• Manage Data Files
• Visually Statistically Analyze Data
• Generate Reports

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SPSS Modules

• Base
• Regressions Models
• Advanced Models
• Tables
• Exact Tests
• Categories

• Trends
• Conjoint
• Missing Values
• Analysis
• Maps

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1.2 Features of Base SPSS

• Friendly, Robust Program Language
• Data Access
• Data Management Manipulation
• Ability to Generate Various Reports
• Ability to Store Programs Reports

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SPSS System Requirements

• System Requirements (Base SPSS)
• Microsoft Windows 98, Me, NT4.0 or 2000
• Pentium-class processor
• 68 Mbytes HD space 64 MRam (min)
• SVGA monitor

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1.3 Basic Concepts

• Typical SPSS Program Flow
• Data
• Syntax
• Output

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Typical SPSS Program Flow

• SPSS Programs are a series of steps
• There are two kinds of steps

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Data Step Functions

• Primary Functions of the Data Step
• Create SPSS data files from external files
• Modify, manipulate or enhance existing SPSS data
  files
• Generate data-related reports (e.g., audits)
• Transfer data

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Data Step Data View
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Data Step Variable View
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Syntax Step
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Output Step
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Workshop

• Getting Started Exploring SPSS
• Open data view
• Open syntax view

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2. Data Management

• 2.1 Using Data Files in SPSS
• 2.2 The SPSS Data Editor
• 2.3 Changing Data Formats
• 2.4 Building a Data Dictionary

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Using Data Files in SPSS

• Exporting a Fixed-format Access File
• Step 1 Export Access table in an
  SPSS-compatible format
• Excel (.xls)
• dBASE, FoxPro (.dbf)

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Exporting an Access Table
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Using Data Files in SPSS

• Importing a Fixed-format Excel File
• Step 2 Open the file in SPSS
• Open SPSS
• Under datasheet view
• Click FILE / OPEN / DATA

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Opening a File in SPSS
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Opening a File in SPSS
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Opening a File in SPSS
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Using Data Files in SPSS

• Saving a Fixed-format SPSS File
• Step 3 Save the file in SPSS (.sav) format

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Workshop

• Export Access file to Excel. Then, import it to
  SPSS
• Get SPSS Training.dbs from C\DCS_SPSS_Training\Tr
  aining Data folder
• Export Custody One to SPSS
• Save the file to Custody One.sav

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Importing .dbf Files to SPSS

• The Current Version of Excel Has a Maximum
  Capacity of 65,000 records
• In Cases Where N gt 65K, Export the File to SPSS
  in .dbf Format.

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Workshop

• Export Access file to .dbf. Then, import to SPSS
• Get SPSS Training.dbs from C\DCS_SPSS_Training\Tr
  aining Data folder
• Explore Client One to SPSS
• Save the file to Client One.sav

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Using Data Files in SPSS

• Importing a Fixed-format Text (.txt) File
• AFCARS Foster Care Data for Federal Government
  Reporting.

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Opening a Text File in SPSS
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Opening a Text File in SPSS
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Opening a Text File in SPSS
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Opening a Text File in SPSS
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Opening a Text File in SPSS
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Opening a Text File in SPSS
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Opening a Text File in SPSS
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Workshop

• Import Sep 02 AFCARS file to SPSS
• Get Sept 2002.txt from C\DCS_SPSS_Training\Traini
  ng Data folder
• Import this file to SPSS
• Save the file to Sept02.sav

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Using Data Files in SPSS

• Importing a Delimited Text (.txt) File
• TNKIDS
• ext__person_demo.txt

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Importing a Delimited File
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Importing a Delimited File
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Importing a Delimited File
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Working with Variables in SPSS

• Rules for Variable Names
• Must be unique
• Length lt 8 characters
• Must begin with a letter
• May include _at_, , _ or
• Cannot end with a period
• Should not end with an underscore
• Cannot include blanks or special characters

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Working with Variables in SPSS

• Creating Variables Types
• Numeric Comma Dot
• Store up to 16 decimal places
• Data view displays only the defined N of decimals
• System uses complete value in all computations
• Date
• Delimiters slash, dash, space, comma or period
• Month values number, 3-character or full name
• Data stored internally from October 14, 1582

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Working with Variables in SPSS

• Creating Variables Types
• String
• Values are right-padded to the maximum width
• String variable with width 6
• No No
• No .NE. No

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Variable Type
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Working with Variables in SPSS

• Creating Variable Labels
• Variable label length lt 256
• FAMCODE AFCARS Family Structure Code
• Can be displayed in all output

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Working with Variables in SPSS

• Creating Value Labels
• Assigns a descriptor to each value
• Very useful with numeric codes that represent
  non-numeric categories
• FAMCODE 01, 02, 03, 04, 05
• 01 Married Couple
• 02 Unmarried Couple
• 03 Single Female

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Value Labels
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Working with Variables in SPSS

• Defining Missing Values
• Defines specified data values as user-missing
• Values can include
• lt 3 discrete values
• 998 Did Not Answer
• 997 Question Not Applicable
• Range of missing values
• Range, plus 1 missing values

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Levels of Measurement

• Nominal
• Alphanumeric variables whose values represent
  categories that have no inherent metric
• Ordinal
• Numeric variables whose values represent a
  hierarchy or rank order
• Level 1 Least Restrictive
• Level 4 Most Restrictive
• Interval/Ratio/Scale
• Numeric variables whose values possess real
  mathematical properties  

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Workshop

• Work on Client One.sav to define variable label
  and values
• Use Appendix 2 to complete the workshop

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2.2 The SPSS Data Editor

• Change data values
• Cut, copy, and paste data values
• Add and delete cases
• Add and delete variables
• Change the order of variables

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2.3 Changing Data Formats

• From string to numeric
• From numeric to string
• Change date format from dd-mmm-yyyy to mm/dd/yyyy

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Workshop

• Open Custody One.save
• Save into Custody Two.sav
• Change Custody_dt format from mm/dd/yyyy to
  dd-mmm-yyyy
• Add one numeric variable Cohort
• Add 3 cases

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2.4 Building a Data Dictionary
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Display of Data Dictionary
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3. Using the SPSS Help Function
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Using the Help Function
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Using the Help Function