Transcript Business Research Methods Template

Data Analysis
Using SPSS
 Muhamad Jantan & T. Ramayah
School of Management, Universiti Sains Malaysia
SPSS-2
What is SPSS?
 General Purpose Statistical Software
 Consists of three components
Data Window - data entry and database
(.sav)
Output Window - all output from any SPSS
session (.lst)
Syntax Window - commands lines (.sps)
 Muhamad Jantan & T. Ramayah
School of Management, Universiti Sains Malaysia
SPSS-3
Data Entry & Preparation
 Data entry
New or Recalled (SPSS or non-SPSS)
 Data Definition
 Data Manipulation and Variable
Development
 Muhamad Jantan & T. Ramayah
School of Management, Universiti Sains Malaysia
SPSS-4
Data Definition
 Purpose:
Give meanings to the numbers for ease of
reading the output
 Involves
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Data Format
Variable Name
Value Labels
Missing Values
Command: Data  Data Definition
 Muhamad Jantan & T. Ramayah
School of Management, Universiti Sains Malaysia
SPSS-5
Data Manipulation
Recoding
To give new values to old values (especially
reversing negatively worded questions)
To form nominal variable from continuous data
Variable Development
To form new variables combinations of old ones
or functions of old ones
Command: Transform  Recode/ Compute
 Muhamad Jantan & T. Ramayah
School of Management, Universiti Sains Malaysia
SPSS-6
Data Analysis - Descriptive
Purpose:
To describe each variable - What is the current
level of the variable of interest?
Command
Frequency
Means, Minimum, Maximum, Standard
Deviation, Quartiles, Standard Deviation
Analyze  Frequencies /Descriptives
 Muhamad Jantan & T. Ramayah
School of Management, Universiti Sains Malaysia
SPSS-7
Data Analysis - Descriptive
Frequencies for two or more nominal
variables
Analyze  Summarize  Crosstabulation
Means of variables by subgroups defined
by one or more nominal variables
Analyze  Compare Means  Means (Use of
Levels)
 Muhamad Jantan & T. Ramayah
School of Management, Universiti Sains Malaysia
SPSS- 8
Parametric
Test of Differences
When
 dependent continuous variable and we want
to test differences across groups
Command
 Analyze  Compare Means  Independent ttest/ Paired t-test/ one-way ANOVA
 Muhamad Jantan & T. Ramayah
School of Management, Universiti Sains Malaysia
SPSS- 9
Non-Parametric Test of
Differences
When
 dependent variable ordinal or normal
assumption not met
Command
 Analyze  Non-parametric  2 Independent/ 2
related samples/ k independent samples/ k
related samples
 Muhamad Jantan & T. Ramayah
School of Management, Universiti Sains Malaysia
SPSS- 10
Parametric Two-Way
ANOVA
When
 continuous dependent variable and related
groups
Command
 Analyze  General Linear Model  Simple
 Note: Fixed Factor Effect
 Muhamad Jantan & T. Ramayah
School of Management, Universiti Sains Malaysia
SPSS- 11
Bivariate Relationship
When
 Covariation between two variables
Correlation:
 When both are continuous or ordinal
Command
Analyze  Correlate  Bivariate (with option
for Spearman if both ordinal)
 Muhamad Jantan & T. Ramayah
School of Management, Universiti Sains Malaysia
SPSS- 14
Regression Analysis
When
 To establish relationship between one
continuous dependent variable and a
number of continuous independent variables
Command
Analyze  Regression  Linear (Use Statistics,
Save options)
Issues:
 Assumptions of Regression - normality;
constant variance, independence of
independent variables; independence of
error terms
 Muhamad Jantan & T. Ramayah
School of Management, Universiti Sains Malaysia
SPSS- 15
Regression Analysis
Issues (cont.)
 Outliers and Leverage Values
 Choice of Selection Method of Independent
Variables - Enter, Backward, Forward,
Stepwise
 Dummy Independent Variables
Options
 Residual Analysis; Influence Statistics,
Collinearity Diagnostics, Normality Plots
 Muhamad Jantan & T. Ramayah
School of Management, Universiti Sains Malaysia
SPSS- 16
Regression Analysis
Interpretation
 Goodness of Model: R2, F-statistics, Adj. R2,
Standard error
 Strength of Influence of Independent
Variables: beta and standardized beta
 Muhamad Jantan & T. Ramayah
School of Management, Universiti Sains Malaysia
SPSS- 17
Discriminant Analysis
When
 Dependent Variable is Nominal and the Purpose
is to predict group membership on the basis of
independent variables
Command
Analyze  Classify  Discriminant (Option:
Classify by summary tables; Select - for holdout
and analysis samples
Issues
 Similar to Regression
 Muhamad Jantan & T. Ramayah
School of Management, Universiti Sains Malaysia
SPSS- 18
Discriminant Analysis
Interpretation
 Goodness of Analysis: Hits Ratio - compared
to maximum chance, proportional chance
and Press Q.
 Univariate Results: To establish the
discriminating variables
 Muhamad Jantan & T. Ramayah
School of Management, Universiti Sains Malaysia
SPSS- 13
Factor Analysis
When
 To reduce the number of variables to
underlying dimensions
Command
Analyze  Data Reduction  Factor (Option:
rotation, save factor scores)
Issues
 Assumptions sufficient correlations between
the variables (Bartlett test; anti-image, KMO
test of sufficiency)
 Muhamad Jantan & T. Ramayah
School of Management, Universiti Sains Malaysia
SPSS- 12
Reliability Analysis
When
 Before forming composite index to a
variable from a number of items
Command
Analyze  Scale  Reliability Analysis (with
option for Descriptives item, scale, scale if
item deleted)
Interpretation
 alpha value greater than 0.7 is good; more
than 0.5 is acceptable; delete some items if
necessary
 Muhamad Jantan & T. Ramayah
School of Management, Universiti Sains Malaysia