Transcript Basic Data Analysis - Villanova University

Exploring
Marketing Research
William G. Zikmund
Chapter 20:
Basic Data Analysis
Descriptive Analysis
• The transformation of raw data into a form
that will make them easy to understand and
interpret; rearranging, ordering, and
manipulating data to generate descriptive
information
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Type of
Measurement
Type of
descriptive analysis
Two
categories
Nominal
More than
two categories
Frequency table
Proportion (percentage)
Frequency table
Category proportions
(percentages)
Mode
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Type of
Measurement
Type of
descriptive analysis
Ordinal
Rank order
Median
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Type of
Measurement
Type of
descriptive analysis
Interval
Arithmetic mean
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Type of
Measurement
Ratio
Type of
descriptive analysis
Index numbers
Geometric mean
Harmonic mean
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Tabulation
• Tabulation - Orderly arrangement of data in
a table or other summary format
• Frequency Table
• Percentages
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Frequency Table
• The arrangement of statistical data in a rowand-column format that exhibits the count
of responses or observations for each
category assigned to a variable
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Central Tendency
Type of Scale
Nominal
Ordinal
Interval or ratio
deviation
Measure of
Central
Tendency
Measure of
Dispersion
Mode
Median
Mean
None
Percentile
Standard
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Cross-Tabulation
• A technique for organizing data by groups,
categories, or classes, thus facilitating
comparisons; a joint frequency distribution
of observations on two or more sets of
variables
• Contingency table- The results of a crosstabulation of two variables, such as survey
questions
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Cross-Tabulation
•
•
•
•
Analyze data by groups or categories
Compare differences
Contingency table
Percentage cross-tabulations
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Base
• The number of respondents or observations
(in a row or column) used as a basis for
computing percentages
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Elaboration and Refinement
• Moderator variable
– A third variable that, when introduced into an
analysis, alters or has a contingent effect on the
relationship between an independent variable
and a dependent variable.
– Spurious relationship
• An apparent relationship between two variables that
is not authentic.
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Quadrant Analysis
Two
rating
scales
4 quadrants
two-dimensional
table
ImportancePerformance
Analysis)
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Data Transformation
• Data conversion
• Changing the original form of the data to a
new format
• More appropriate data analysis
• New variables
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Data Transformation
Summative Score =
VAR1 + VAR2 + VAR 3
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Collapsing a Five-Point Scale
• Strongly Agree
• Agree
• Neither Agree nor
Disagree
• Disagree
• Strongly Disagree
• Strongly Agree/Agree
• Neither Agree nor
Disagree
• Disagree/Strongly
Disagree
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Index Numbers
• Score or observation recalibrated to indicate
how it relates to a base number
• CPI - Consumer Price Index
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Calculating Rank Order
• Ordinal Data
• Brand Preferences
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Tables
• Bannerheads for columns
• Studheads for rows
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Charts and Graphs
• Pie Charts
• Line Graphs
• Bar Charts
– Vertical
– Horizontal
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Line Graph
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Bar Graph
100
80
60
East
40
W est
20
N orth
0
1st
2nd
3rd
4th
Q tr
Q tr
Q tr
Q tr
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Computer Programs
•
•
•
•
SPSS
SAS
SYSTAT
Microsoft Excel
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Computer Programs
• Box and Whisker Plots
• Interquartile range - midspread
• Outlier
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Interpretation
• The process of making pertinent inferences
and drawing conclusions
• concerning the meaning and implications of
a research investigation
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