FEBRUARY, 2013

BY: ABDUL-RAUF

A TRAINING WORKSHOP ON STATISTICAL AND PRESENTATIONAL

SYSTEM SOFTWARE (SPSS) 18.0 WINDOWS

Introduction

Mathematics is the language of science, data analysis is the language of research

As long as there is research, there will be the need to analyze data

SPSS - Statistical and Presentational System Software

SPSS 17 and 18 are called PASW (Predictive Analytics SoftWare)

What is SPSS? A software package use for conducting statistical analysis,

manipulating data, and generating tables and graphs.

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Getting to know SPSS

Option 1: Place your cursor on the SPSS icon and double

click

Option 2: Step 1: Click on Start Step 2: Move cursor to All Programmes Step 3: Click on SPSS executable file to open Step 4: Click on the option under ‘What would

you like to do’? E.g Open existing data source

Step 5: Click OK button

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Features of SPSS

The main window features include:

Data Editor

Data view and Variable view

The Viewer

The Pivot Table Editor

Chart EditorSeTRAC

Entering data

Step 1: Click on Data View Step 2: Click on the first cell (1st C, 1st R) Step 3: Type in the # e.g. if the variable is ID,

then type in 1 Step 4: Move the cursor into the second cell

and enter second piece of information for case # 1

Step 5: Move the cursor into next cell and enter very piece of information for case # 1

Step 6: Press the Home key to get back. Use the down arrow to move to the second row and enter data for case #2

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Modifying the data file

To delete a caseTo insert a case between existing casesTo delete a variableTo insert a variable between existing

variablesTo move an existing variableTo sort the data fileTo split the data fileTo select cases

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To insert a variable between existing variables

Step 1: Position your cursor in a cell in the column (variable) to the right of where you would like the new variable to appear

Step 2: Right click

Step 3: Insert variable

Step 4: Enter the data of the new variable

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To move an existing variable

Step 1: Create a new empty variable column

Step 2: Click on the variable name of the existing variable you wish to move

Step 3: Click on the Edit menu and choose Cut

Step 4: Highlight the new empty column that you created

Step 5: Click on the Edit menu and choose Paste

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Screening and cleaning the data

Data screening process involves a # of steps:

Step 1: Checking for errors

Step 2: Finding the error in the data file

Step 3: Correcting the error in the data file

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Checking for errors

Inspect the frequencies for Categorical variables

Click on Analyze Click on Descriptive StatisticsClick Frequencies Choose the variable you wish to check (e.g. sex)Move these into the Variables boxClick on Continue Click on OK

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Checking for errors cont.

Inspect the frequencies for Continuous variables

Click on Analyze Click on Descriptive StatisticsClick Descriptives Choose the variable you wish to check (e.g. age)Move these into the Variables boxClick on Continue Click on OK

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Checking for errors cont.

Step 1: Check your minimum, maximum and means values

Step 2: Check the number of valid and missing cases

Step 3: Check the frequencies fall into each category eg district, community, etc

Step 4: Delete on your keypadSeTRAC

Finding the error in the data file

METHOD 1Step 1: Click on the variable name of the variable

in which the error has occurred (e.g. a 3 for sex)Step 2: Click once to highlight the columnStep 3: Click on Edit from the menu across the

top of the screenStep 4: click on FindStep 5: In the Search for box, type in the

incorrect value that you are looking for (e.g 3)Step 6: Click on Search Forward to continue

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Finding the error in the data file

METHOD 2 Step 1: Click on Analyze, Descriptive Stat. Explore Step 2: In the Display section click on Statistics Step 3: Click on e.g. sex and move to Dependent

list Step 4: In the Label cases, choose ID Step 5: In the Statistics section choose Outliers Step 6: Click on Continue Step 7: In the Options section choose Exclude case

pairwise Step 8: Click on Continue and then OK

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Correcting the error in the data file

Step 1: Check what value should have been entered for that person

Step 2: Find the variable labelled IDStep 3: Move down to the case that has the

ID # with the errorStep 4: Move across the row until you come

to the column of the variable with the errorStep 5: Place the cursor in the cell, type in

the correct value

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Obtaining frequency for categorical variable

Step 1: Click on Analyze, Descriptive Statistics, Frequency

Step 2: Choose and highlight the categorical variables you are interested in

Step 3: Move these into the Variables boxStep 4: Click on the Statistics buttonStep 5: In the Dispersion section tick

Minimum and MaximumStep 6: Click on Continue and OK

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Obtaining descr. stat. for continuous variable

Step 1: Click on Analyze, Descriptive Statistics, Descriptives

Step 2: Click on all the continuous variables that you wish to obtain descriptive statistics for

Step 3: Click on the arrow button to move them into the Variables box

Step 4: Click on the Options buttonStep 5: Click on mean, standard deviation,

minumum, maximum, skewness, kurtosisStep 6: Click on Continue, and OK

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Cross tabulation

Step 1: Click on Analyze, Descriptive Statistics, Cross tabs

Step 2: Click on (sex)Step 3: Click on Row arrow button to move

into Row(s) sectionStep 4: Click on (agegp3) Step 5: Click on Column arrow button to

move into Column(s)Step 6: Click on Cells

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Crosstab cont.

Step 7: Click on Expected, Total, Unstandardized

Step 8: Click on ContinueStep 9: Click on OK

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Creating graphs e.g. histogram

Step 1: Click on Graphs, HistogramStep 2: Click on your continuous variable

of interest (Total perceived stress)Step 3: Move it into the Variable boxStep 4: Click on Display normal curveStep 5: Click on Title to type the desired

titleStep 6: Click on Continue and OK

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Bar graph

Step 1: Click on Graph, BarStep 2: Click on ClusteredStep 3: In the Data in chart are section,

click on Summaries for groups of casesStep 4: Click on DefineStep 5: In the Bars represent box click on

Other statistics/summary functionStep 6: Click on the continuous variable

(Total perceived stress)Step 7: Click on categorical variable (agegp3)SeTRAC

Bar graph cont.

Step 8: Click on the arrow button to move it into the Category axis box

Step 9: Click on another categorical variable (sex)

Step 10: Move it into the Define Clusters by box

Step 11: Click on the Options buttonStep 12: Remove tick if any from Display

groups defined by missing valuesStep 13: Click on OKSeTRAC

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Creating a scatterplot

Step 1: Click on Graphs, Scatter Step 2: Click on Simple, Define Step 3: Click on your dependent variable (Total

perceived stress) Step 4: Click on the arrow to move it into the box

labelled Y axis Step 5: Move your other variable into the box

labelled X axis Step 6: Move categorical variables into the Set

Markers by box Step 7: Click on Title, Continue and then OKSeTRAC

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Editing a chart/graph

Step 1: Double click on what you wish to change

Step 2: Click on the title or label you wish to change

Step 3: Click once on the aspect of the chart/graph that you wish to change

Step 4: Click on the button on the menu bar that corresponds to the aspect you wish to change

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Non-parametric techniques

There are many techniques of non-parametrics

Chi-square for independenceMann-Whitney TestWilcoxon Signed Rank TestKruskal-Wallis TestFriedman TestSpearman Rank Order Correlation

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Procedure for Spearman’ Rank Order Cor.

Step 1: Click on Analyze, Correlate, Bivariate

Step 2: Click on your two variables (total PCOISS, total perceived stress)

Step 3: Move them into the box marked Variables

Step 4: In the section labelled Correlation Coefficients

Step 5: Click on the option labelled Spearman

Step 6: Click on OKSeTRAC

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THE END

THANK YOU FOR YOUR ATTENTION

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