spss

Statistical Analysis Using SPSS

Mithun Kumar Acharjee

Lecturer in StatisticsDepertment of International Business

Faculty of Businesss StudiesUniversity of Dhaka

June 25, 2014

Brief Knowledge in SPSS

History:

First devised in 1966

Developed as an analysis program for social scientist

SPSS-Statistical Package for Social Science

SPSS-Superior Performing Software System (Modern name)

Function:

1 Data entry

2 Manipulate and manage data

3 Produce reports and tables

4 Perform simple and complex statistical analysis

5 Produce graphical output

Mithun Kumar Acharjee Statistical Analysis Using SPSS 2 / 14

Brief Knowledge in SPSS

Various types of files in SPSS:

1 SPSS data file-Extension-SAV

2 SPSS syntax file-Extension-SPV

3 SPSS output file-Extension-SPO

Naming a variable in SPSS:

The name of the variable should be short in size. You may use analpha-numeric name.

you may use underscore or dot between two words if the name islong, but can’t use space or dash.


Scale of measurement:Statistical data, whether qualitative or quantitative, are generatedobtained through some measurement or observational processes. Thereare four scale of measurement. Each type of measurement has uniquecharacteristics and implications for the type of statistical procedures thatcan be used with it. These are-

1 Nominal scale

2 Ordinal scale

3 Interval scale

4 Ratio scale

Nominal scale:Arithmetic: CountingFeatures: CategoriesExamples:Religion, sex.


Ordinal scale:Arithmetic: Counting, RankingFeatures: Categories, RanksExamples:Economic status, education status.

Interval scale:Arithmetic: Counting, Ranking, Addition, SubtractionFeatures: Categories, Ranks, has equal unitsExamples:I.Q. score, Temperature

Ratio scale:Arithmetic: Counting, Ranking, Addition, Subtraction, Multiplication,DivisionFeatures: Categories, Ranks, has equal units, has absolute zeroExamples: Family size


Data Management

Data Management contains Data Manipulation and Data Transformation.

Data Manipulation:Data manipulation contains:

1 Inserting Variables

2 Inserting cases

3 Go to case/variables

4 Merging Files

5 Splitting File

6 Case selection

7 Selecting a random sample


Data Transformation

Contents:

Computing Variables

Functions

Missing Values in Functions

Random Number Generators

Occurrences of Values within Cases

Shift Values

Recode into Same Variables

Recode into Different Variables

Automatic Recode

Rank Cases

Date and Time Wizard

Time Series Data Transformations


Data Transformation

Use the Compute dialogue box to compute values for a variable based onnumeric transformations of other variables.

You can compute values for numeric or string (alphanumeric)variables.

You can create new variables or replace the values of existingvariables. For new variables, you can also specify the variable typeand label.

You can compute values selectively for subsets of data based onlogical conditions.

You can use a large variety of built-in functions, including arithmeticfunctions, statistical functions, distribution functions, and stringfunctions.


Data Transformation

To compute values:From the menus choose:

Transform ¿ Compute Variable...

Type the name of a single target variable. It can be an existingvariable or a new variable to be added to the active dataset.

To build an expression, either paste components into the Expressionfield or type directly in the Expression field.

You can paste functions or commonly used system variables byselecting a group from the Function group list and double-clickingthe function or variable in the Functions and Special Variables list(or select the function or variable and click the arrow adjacent to theFunction group list). Fill in any parameters indicated by questionmarks (only applies to functions). The function group labelled Allprovides a listing of all available functions and system variables. Abrief description of the currently selected function or variable isdisplayed in a reserved area in the dialogue box.


Data Transformation

Compute Variable: If Cases:The If Cases dialog box allows you to apply data transformations toselected subsets of cases, using conditional expressions. A conditionalexpression returns a value of true, false, or missing for each case.

If the result of a conditional expression is true, the case is includedin the selected subset.

If the result of a conditional expression is false or missing, the case isnot included in the selected subset.

Most conditional expressions use one or more of the six relationaloperators on the calculator pad.

Conditional expressions can include variable names, constants,arithmetic operators, numeric (and other) functions, logicalvariables, and relational operators.


Data Transformation

Compute Variable: Type and Label:By default, new computed variables are numeric. To compute a newstring variable, you must specify the data type and width.

Label: Optional, descriptive variable label up to 255 bytes long. You canenter a label or use the first 110 characters of the compute expression asthe label.

Type: Computed variables can be numeric or string (alphanumeric).String variables cannot be used in calculations.


Data Transformation

Recode into same variables:The Recode into Same Variables dialog box allows you to reassign thevalues of existing variables or collapse ranges of existing values into newvalues. For example, you could collapse salaries into salary rangecategories.To Recode Values of a VariableFrom the menus choose:

Transform ¿ Recode into Same Variables...

Select the variables you want to recode. If you select multiplevariables, they must be the same type (numeric or string).

Click Old and New Values and specify how to recode values.


Data Transformation

Recode into Same Variables: If Cases:The If Cases dialog box allows you to recode values for a selected subsetof cases, using conditional expressions. A conditional expression returns avalue of true, false, or missing for each case.

If the result of a conditional expression is true, the case is includedin the selected subset.

If the result of a conditional expression is false or missing, the case isnot included in the selected subset.

Most conditional expressions use one or more of the six relationaloperators (¡, ¿, ¡=, ¿=, =, and =) on the calculator pad.

Conditional expressions can include variable names, constants,arithmetic operators, numeric (and other) functions, logicalvariables, and relational operators.


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