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Md. Abdullah Al Mahmud Senior Lecturer
Manarat International University
Lecture-1 Introduction to SPSS
What is SPSS?
The statistical package SPSS was first devised in 1966. Actually SPSS was developed as an
analysis program for social scientists.
SPSS [Statistical Package for Social Sciences] is a program that allows us to describe and
analyze data.
Analysis of data using SPSS
Proficiency with statistical software package is indispensable today for research in Business.
SPSS is one of the most widely used and powerful statistical software packages. It covers a
broad range of statistical procedures that allow us to summarize data (e.g mean, standard
deviation, CV), examine relationships among variables (e.g. correlation, regression), determine
whether there are significant difference between groups (e.g t-test, z-test, ANOVA), and
graphical presentation of results (e.g bar chart, line chart, histogram). It can easily perform
almost any statistical analysis.
What can SPSS do?
manipulate and manage data
produce reports and tables
perform simple and complex statistical analyses
produce graphical output
SPSS for windows: Getting started
You can start SPSS either by clicking on SPSS for windows in the Programs of start button or by
double clicking its shortcut icon.
Md. Abdullah Al Mahmud Senior Lecturer
Manarat International University
What do we see first?
Once SPSS has been initialized the first screen which we see in SPSS will look like that in the figure1.1. This first window is the Data Editor. Here we enter data and save it as a data file. To begin with it is called Untitled- SPSS Data Editor. This indicates that this is a new and as yet, empty data file.
Figure 1.1: SPSS initial screen display-The Data Editor
Composition of the Data File
The topmost along the top of the screen we see the Menu Bar is used to access all the commands available. The Menu Bar has a number of headings, splitting the commands into categories of similar functions (File, Edit, View, Data, Transform, Analyze, Graphs, Utilities, Window, and Help).
Md. Abdullah Al Mahmud Senior Lecturer
Manarat International University
Data:
A data set is the organized or structured form of information obtained from experiments, surveys
or other sources. Before starting data analysis in SPSS, it is important to be clear about how the
variables are recorded for each case individual.
Note that: In the Data Editor window of SPSS each column will represent a variable and each
row will stand for a case or respondent or individual.
Creating the Data File
Here is the step-by-step procedure for creating data file with the help of the following example.
Data on 10 individuals collected in a study are presented in table1.2
Table1.1: Diastolic and Systolic BP, Blood Glucose and income for 10 subjects
Subject no.
Gender Religion Diastolic BP
Systolic BP
Blood Glucose
Income(Tk)
1 Male 1 90 120 6.7 5000
2 Female 1 100 130 5.5 10000
3 Female 2 85 125 7.5 40000
4 Male 1 80 110 8.0 20000
5 Female 3 75 150 6.2 15000
6 Male 4 90 120 8.5 60000
7 Male 1 65 140 9.0 3000
8 Male 3 60 150 7.2 1000
9 Female 1 95 135 5.6 50000
10 Female 2 100 110 7.1 100000
Md. Abdullah Al Mahmud Senior Lecturer
Manarat International University
Creating Variables:
To create variable(s) we need to follow the steps below:
1. On the bottom of left hand corner of the Data Editor Window simply click on Variable View
(Figure 1.2)
2. In the space for Name, type the desired variable name, this can be no more than 8 characters
in length. The first character must be alphabetic; the remaining characters can be alphabetic and /
or numeric, and no spaces can appear in the name. So, in this case, let’s type Name.
3. We should then through the relevant columns for that particular variable.
4 Click on the gray portion following String.
Figure 1.2: Variable View Window.
Md. Abdullah Al Mahmud Senior Lecturer
Manarat International University
Functions of the columns and the default values of a variable view window:
Default values
a. Type: Allows defining the type of variable, Numeric
b. Width: Total number of characters, 8
c. Decimals: Number of characters beyond the decimal point, 2
d. Label: A name for the variable that can be up to 120 characters long and can include spaces (which variable names cannot). If a variable label is entered, the label will be printed on charts and reports instead of the name, making them easier to understand.
Allows to list a more extensive label for our variable. Eight character variable names are difficult
to remember, and we always exercise the option of listing a more descriptive label.
None
e. Value: Allows providing labels for the various label of a variable. None
It provides a key to translate numeric data.
To change the variable label, click on the Labels… button. This will open the Define Labels: dialog box. Enter the appropriate information into the fields. When done, click on the Continue button.
f. Missing values: This field indicates which subset of the data will not be included in the data set. To change this field, click on the Missing Values… button. This will open the Define Missing Values: dialog box. Enter the appropriate information into the fields. When done, click on the Continue button.
That Enables designate certain scores as missing. None
Md. Abdullah Al Mahmud Senior Lecturer
Manarat International University
g. Columns: Allows changing the maximum number of characters in a column.
8
h. Align: Allows determining the alignment of column. Right
Measure: Allows determining the kind of scale for that particular variable. Scale
Nominal data: are categories that have no numerical meaning such as one's religious
denomination or city or residence. The values can't logically be added, subtracted, or even sorted.
Ordinal data: are categories also, but they can be sorted in some logical fashion such as class
(freshman, junior, senior).
Md. Abdullah Al Mahmud Senior Lecturer
Manarat International University
.
Figure1.3: Variable type dialog box.
5. Click on label and type the Name of the respondent
6. If necessary perform other options such as modify the column width and whether the numbers
appear left justified, right justified, or centered.
Md. Abdullah Al Mahmud Senior Lecturer
Manarat International University
Figure1.4: SPSS Data Editor with Value Labels dialog box.
Md. Abdullah Al Mahmud Senior Lecturer
Manarat International University
Figure1.5: SPSS Data File showing the variables.
Md. Abdullah Al Mahmud Senior Lecturer
Manarat International University
Figure1.6: SPSS Data Editor showing the values for different variables.
Descriptive Statistics:
Descriptive statistics includes the measures of both location (mean, median, mode etc.) and
dispersion (range, SD etc). The following are considered when computing descriptive statistics.
Mean and standard deviation are often used when data are assumed normal
Median and range are normally used in case of data containing extreme values
The mode is useful for nonnumeric data.
We shall describe the step-by-step procedures using data from example for computing
descriptive statistics.
Md. Abdullah Al Mahmud Senior Lecturer
Manarat International University
Frequencies:
To begin, click on
Analyze
Descriptive Statistics
Frequencies
Figure: 1.7: SPSS data editor showing the path to the option Frequencies
Selecting variables:
Md. Abdullah Al Mahmud Senior Lecturer
Manarat International University
1. Click on [Analyze => Descriptive Statistics => Frequencies] which gives Frequencies dialog
box (Figure 1.8)
2. Select the variables from the list on the left in the frequencies dialog box
3. Click on arrow to move the variable to the window on the right
Specify Statistics:
4. Select Statistics that yield Frequencies: Statistics dialog box. Select required statistics.
5. Click continued and finally OK
Figure: 1.8: Frequencies and Frequencies: Statistics dialog box
Md. Abdullah Al Mahmud Senior Lecturer
Manarat International University
Figure:1.9: Output showing important statistics and Frequency table
What are the different types of windows in SPSS?W?
There are three kinds of windows in SPSS.
Data Editor Window: This is the first window that will appear when you start an SPSS session. The Data Editor Window is used to define and enter data and to perform statistical computations.
Output Window: The results of the statistical test appear in the Output Window.
Syntax Window: The Syntax Window can be used to keep a record of the operations that we perform on our data. This window is automatically opened when we click a Paste function.
Md. Abdullah Al Mahmud Senior Lecturer
Manarat International University
Different SPSS windows and their functions:
Windows Function
Data Editor Used to define, enter, and edit data and to run statistical tests
Output Contains the results of the statistical procedures
Syntax Activate when we click on the Paste function and record of the operations