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LINDSEY BREWER

CSSCR (CENTER FOR SOCIAL SCIENCE COMPUTATION AND RESEARCH)

UNIVERSITY OF WASHINGTON

September 17, 2009

Introduction to SPSS

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Topics we will cover today

SPSS at a glance

Basic Structure of SPSS

Cleaning your data

Descriptive Statistics

Charts

Data manipulation

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SPSS at a glance

SPSS stands for Statistical Package for the

Social Sciences

SPSS was made to be easier to use then other

statistical software like S-Plus, R, or SAS.

The newest version of SPSS is SPSS 17.0.

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How to open SPSS

Go to START

Click on PROGRAMS

Click on SPSS INC

Click on SPSS 16.0

The computers in the CSSCR lab typically have SPSS

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Opening a data file

Click on FILE

OPEN

DATA

Click MY COMPUTER

LOCAL DISK C:/

Click PROGRAM FILES

SPSS

Click TUTORIAL

SAMPLE FILES

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Basic structure of SPSS

There are two different windows in SPSS

1

st

– Data Editor Window - shows data in two forms

 Data view

 Variable view

2

nd

– Output viewer Window – shows results of data

analysis

 *You must save the data editor window and output viewer

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Data view vs. Variable view

Data view

Rows are cases

Columns are variables

Variable view

Rows define the variables

 Name, Type, Width, Decimals, Label, Missing, etc.

 Scale – age, weight, income

 Nominal – categories that cannot be ranked (ID number)  Ordinal – categories that can be ranked (level of

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Cleaning your data – missing data

There are two types of missing values in

SPSS: system-missing and user-defined.

System-missing data is assigned by SPSS

when a function cannot be performed.

For example,

dividing a

number by

zero. SPSS

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User-defined missing data are values that the researcher can tell SPSS to recognize as missing. For example, 9999 is a common user-defined missing value. To define a variable’s user-defined missing value…

Cleaning your data – missing data

Look at your variables in VARIABLE

VIEW

Find the column labeled MISSING

Find the variable that you would like to

work with.

Select that variable’s missing cell by

clicking on the gray box in the right corner.

click DISCRETE MISSING VALUESenter 9999 to define this variable’s

missing value

A range can also be used if you only

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Cleaning your data – missing data cont.

When you have missing data in your data set, you

can fill in the missing data with surrounding

information so it does not affect your analysis.

click TRANSFORM

click REPLACE MISSING

VALUES

select the variable with

missing values and move it to the right using the arrow

SPSS will rename and create

a new variable with your filled in data.

click METHOD to select what

type of method you would like SPSS to use when replacing missing values.

click OK and view your new

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Descriptive Statistics

Lets say we are interested

in learning more about the

number of customer service

representatives (

service).

Click ANALYZE

Click DESCRIPTIVE

STATISTICS

Click FREQUENCIES

Choose

service

from the

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Descriptive Statistics continued

Lets learn more about the

number of catalogs mailed

(mail)

.

Click ANALYZE

Click DESCRIPTIVE STATISTICS

Click DESCRIPTIVES

Move

MAIL

over with the arrow

Click OPTIONS – we can choose which statistics we are

interested in looking at

We should remember that these descriptive statistics will

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Graphing Data

Click GRAPH

Click CHART BUILDER

Click HISTOGRAM

Put MEN on the X axis.

Click ELEMENT PROPERTIES.

Check the box labeled DISPLAY NORMAL CURVE. This will

impose a normal curve onto your graph. You can also change the style of your graph in this

element properties window.

You can copy and paste these

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Graphing Continued

There are other ways to

make graphs.

Click ANALYZE

Click DESCRIPTIVE

STATISTICS

Click FREQUENCIES

Click

services

Click CHART

Click BAR CHART

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By selecting cases,

the researcher can

select only certain

cases for analysis

click DATA

click SELECT

CASES

click RANDOM

SAMPLE OF CASES

select your

preferences

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Data manipulation – compute new

variable

Computing new variables – create

a new variable from multiple variables

click TRANSFORMclick COMPUTE

fill in the new target variable

TOTALSALES

fill in numeric expression =

men+women+jewel

create an IF statement by

clicking on the IF button

click INCLUDE IF CASE

SATISFIES CONDITION

enter condition MAIL>10000

This new variable

TOTALSALES

tells us what the total sales

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Data manipulation in action!

Try creating another variable for

TOTALSALES2

for catalogs which

mailed under 10,000 catalogs.

Try comparing the descriptive statistics

of

TOTALSALES

and

TOTALSALES2.

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Recoding allows a researcher to create a new

variable with a different set of parameters

click TRANSFORM

click RECODE INTO DIFFERENT VARIABLE

Data manipulation – recode a

variable

move

mail

over

to the right

create a name

for the new

variable

mailcategories

click OLD AND

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click RANGE

to create

ranges of old

values

click VALUE

to create a

new value for

that range

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Data manipulation in action!

Try recoding another variable on

your own.

Try finding the descriptive

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Dummy variables is a variable that has a

value of either 0 or 1 to show the absence or

presence of some categorical effect

Data manipulation – create a dummy

variable

To create a dummy

variable…

click TRANSFORM

click RECODE INTO

DIFFERENT

VARIABLE

click OLD AND NEW

VALUES

click RANGE to

create range of old

values

click VALUE to set

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What we have learned!

SPSS at a glance

Basic Structure of SPSS

Cleaning your data – missing data

Descriptive Statistics –

frequencies, descriptive statistics

Charts

Data manipulation – select cases,

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Other Resources

There are many resources online to help you

learn SPSS (tutorials, blogs, etc.)

CSSCR has a Quicktime SPSS class on its

website

CSSCR offers SPSS handouts which are also on

its website

CSSCR offers classes on SPSS each quarter –

Referencias

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