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STATISTICAL PACKAGESSTATISTICAL PACKAGES

COURSE TEACHER

S. A. AHSAN RAJONCOMPUTER SCIENCE AND ENGINEERING DISCIPLINE,

KHULNA UNIVERSITY, KHULNA.

EMAIL: ahsan.rajon@gmail.com

WEB: www.cseku.ac.bd/rajon

www.rajon.forumerzone.com

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TopicsTopics

COMPUTING VARIABLES

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COMPUTE NEW VARIABLE FROM EXISTINGCOMPUTE NEW VARIABLE FROM EXISTING

It is possible to compute a new variable from oneor more existing variables.

For example, we may define a new variablegpa_1_2 which will contain the average ygpa of 1styear and 2nd year.

That is,Gpa_1_2 = (y1_gpa + y2_gpa) / 2

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COMPUTE NEW VARIABLE FROM EXISTINGCOMPUTE NEW VARIABLE FROM EXISTING

For the overall purpose, Go toTransform -> compute

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COMPUTE NEW VARIABLE FROM EXISTINGCOMPUTE NEW VARIABLE FROM EXISTING

Select the operands from the variable list and use the operatorbuttons as you need in the Compute Variable Window

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COMPUTE NEW VARIABLE FROM EXISTINGCOMPUTE NEW VARIABLE FROM EXISTING

HAVE A LOOK.

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COMPUTING VARIABLESCOMPUTING VARIABLES

BASIC COMMAND:

NEW VARIABLE = MATHEMATICAL EXPRESSION

SPSS mathematical expression may includearithmetic operators:

+ Addition - Subtraction

* Multiplication

/ Division ** Exponential

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COMPUTING VARIABLESCOMPUTING VARIABLES

Mathematical Expression may also containfunctions.

Arithmetic Functions Statistical Functions

Logical Functions

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COMPUTING VARIABLESCOMPUTING VARIABLES

Arithmetic Function

LG10

10 base Logarithm Eg. lginc= LG10(inc)

Calculate logarithm of inc and store into variable lginc

LN

Base e logarithm

Eg. lgeinc= LN(inc)

Calculate e-based logarithm of inc and store into variable

lgeinc

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COMPUTING VARIABLESCOMPUTING VARIABLES

STATISTICAL FUNCTION

SUM

Calculate Summation totinc = SUM(basic, hsrent,bonus)

MEAN

Calculate mean i.e. average.

avgmark = MEAN(mark1 TO mark5)

MEAN is used to calculate the average of mark1, mark2,mark3, mark4, mark5.

The keyword TO can be used to indicate that variables (inorder they are found in the file) in between the twonamed in the command should be included.

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COMPUTING VARIABLESCOMPUTING VARIABLES

LOGICAL FUNCTIONS

Logical functions evaluate as TRUE or FALSE.

IfTRUE, new computed variable will be given the value 1.

IfFALSE, new computed variable will be given the value 0.

ANY

spsscrs = ANY (course, CSE1100, CSE2251, CSE3251, CSE3255)

RANGE

passed = RANGE (marks, 40, 100)

A new variable named passed will be created where, marks with

values more than 40 and less than 100 will be displayed as 1 and

all other cases (< 40) will be presented as 0

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COMPUTING VARIABLESCOMPUTING VARIABLES

Here is a look.

Initially we have this statistics

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COMPUTING VARIABLESCOMPUTING VARIABLES

GO to

TRANSFROM

COMPUTE

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COMPUTING VARIABLESCOMPUTING VARIABLES

Here is theExpression

Passesd

=

RANGE (marks, 40,100)

Click on OK.

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COMPUTING VARIABLESCOMPUTING VARIABLES

Ya.

We getthat

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COMPUTING VARIABLESCOMPUTING VARIABLES

Nowcustomizethat

according tothis look.

But HOW????

Its up toyou.

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COMPUTING VARIABLESCOMPUTING VARIABLES

THANKS !!!