Introduction to SPSS Module II

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Introduction to SPSSModule II

• 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

• Review Module 1
• File Manipulation Functions
• Data Transformation Functions
• Working with Command Syntax

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Review of Module I

• SPSS Program Flow
• Data ? Syntax ? Output
• Using Data Files in SPSS
• Importing a Fixed-length File (.dbf/.xls)
• Importing a Fixed-length Text File (.txt)
• Importing a Variable-length Text File

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Review of Module I

• Working with Variables in SPSS
• Variable Names
• Variable Types
• Variable Labels
• Value Labels
• Missing Values
• Levels of Measurement
• Using the SPSS Data Editor

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File Manipulation Functions

• SPSS File Manipulation Functions
• Sort Cases
• Merge Files
• Select Cases
• Split File
• Restructure Data

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Sort Cases

• Sorts on Sorting Variables gt 1
• Ascending or Descending Order
• Multi-sort SPSS Sorts by Each Variable w/in
  Categories of Prior Variable
• For String Variables, Y Precedes y

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Sort Cases
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Sort Cases
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Merge Files

• Merge File Methods
• Merge files with the same variables, but
  different cases
• Merge files with the same cases, but different
  variables

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Add Cases
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Add Cases
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Add Cases
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Add Cases Workshop

• Merge cases from Cohort2 with Cohort1
• Get Cohort2.sav from C\DCS_SPSS folder
• Sort ID and save the file
• Get Cohort1.sav from C\DCS_SPSS folder
• Sort ID and save the file
• Add cases in Cohort2.sav to Cohort1.sav
• Save the file to Cohort12.sav

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Add Variables
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Add Variables
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Add Variables
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Add Variables
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Add Variables Workshop

• Merge Variables from Custody1.sav with
  Clientall.sav

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Select Cases

• Select Cases Creates Case Subgroups Based on
  Specified Criteria
• Variable values and ranges
• Date and time ranges
• Case numbers
• Arithmetic expressions
• Logical expressions
• Functions

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Select Cases
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Select Cases
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Select Cases Workshop

• Use Casestudy.sav
• Use the Select Cases Function on the Following
  Criteria
• Race21
• Gender11

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Split File

• Splits File into segments based on the value of
  gt 1 grouping variables
• Can specify lt 8 grouping variables
• Cases should be sorted by values of the grouping
  variables in the same order that variables are
  listed in the group based on list.

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Split File
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Split File
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Split File Workshop

• Use Casestudy.sav
• Use the Split File Function on Race2 to separate
  race groups

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Transformation Functions

• Automatic Recode
• Recode Values
• Compute Variable
• Time Series Transformation
• Rank Cases
• Categorize Variables

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Automatic Recode

• Modifies Data Values by Recoding
• Used to combine/collapse categories
• Two Recode Options
• Recode into the same variable
• Recode into a new variable

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Automatic Recode
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Automatic Recode
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Automatic Recode
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Recode Values

• Recode
• Single values
• Range of values
• Missing values
• Recodes Old Value ? New Value

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Recode Values
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Recode Values
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Recode Values
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Recode Values Workshop

• Use Actcase.sav
• Recode RACE ? RACE2
• 1 White
• 2 Black
• 3 Multiple Races
• 4 Other
• 9 Missing
• Recode HISP ? HISP2
• 1 Yes
• 2 No
• 9 Missing

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Compute Variable

• Compute converts values based on the value of
  other variables
• Compute values for numerics or strings
• Create new or replace existing variables
• Compute values using logical conditions
• Can utilize 70 built-in functions

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Compute Variables
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Compute Dates

• Length of Stay BASEDATE - INTDT
• BASEDATE Value YRMODA (yr,mo,dy)
• INTDT Value YRMODA (yr,mo,dy)

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Compute Workshop

• Use Casestudy.sav
• Use the variable of CSIND to Calculate the Number
  of Days in Custody (LOS)
• BASEDATE 11/15/2002

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Rank Cases

• Rank Cases Creates New Variables Containing
  Ranks, Scores or Percentiles
• Can rank cases in either a/d order
• Can organize rank by grouping variables
• Offers several ranking types
• Offers several methods for ranking ties

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Rank Cases
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Rank Cases
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Rank Cases
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Categorize Variables

• Converts Continuous Numeric Data to a Discrete
  Number of Categories
• Categories are based on percentile groups
• Each group contains roughly the same N

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Categorize Variables
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Restructure Data

• Restructure Data Replaces the Current File with a
  New Restructured File.
• Three restructuring methods
• Restructure selected variables into cases
• Restructure selected cases into variables
• Transpose all data

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Restructure Rows to Columns

• In Variable View Change the Format of CNT from
  F2.0 to F4.2

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Restructure Rows to Columns
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Restructure Rows to Columns
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Restructure Rows to Columns
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Restructure Rows to Columns
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Restructure Rows to Columns
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Restructure Rows to Columns
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Restructure Rows to Columns
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Restructure Workshop

• Restructure Data File
• Get F2FTemp.sav from C\DCS_SPSS folder
• Restructure data file from children with multiple
  rows of custody episode to single row with
  multiple columns.

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Working with Command Syntax

• Command Syntax Rules
• Creating Syntax from Dialog Boxes
• Running Command Syntax

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Command Syntax Rules

• Every Command Must Begin On New Line
• Every Command Must End With a Period
• Slashes Separate Most Subcommands
• Command Must Include Full Variable Names
• Text Within Apostrophes or Quotation Marks Must
  Fit On a Single Line

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Command Syntax Rules

• Command Lines Must Be lt 80 Characters
• Command Lines Must Use Periods for Decimals
• Do Not Use Variable Names That End With Periods

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Command Syntax Rules
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Creating Syntax from Dialog
Click Paste to enter syntax from a dialog box to
a syntax window
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Creating Syntax from Dialog
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Running Command Syntax

• Highlight Command in Syntax Window
• Click Run on Syntax Window Toolbar
• Select Choice(s) from Run Menu

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Running Command Syntax

• All
• Runs all commands in the syntax window.
• Selection
• Runs the currently selected command(s) only.
• Current
• Runs command where the cursor is currently
  located.
• To End
• Runs all commands from the cursors current
  location to the end of the command syntax

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Running Command Syntax
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Command Syntax Workshop

• Open the Syntax File
• Custody_Pattern.sps
• Run the Syntax by Section
• Review the Output File
• Debug the Syntax Command File