Download Chapter 20

Business
Research Methods
William G. Zikmund
Chapter 20:
Basic Data Analysis: Descriptive
Statistics
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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
OR DISAGREE
• DISAGREE
• STRONGLY
DISAGREE
• STRONGLY
AGREE/AGREE
• NEITHER AGREE
OR 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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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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