Measurement To collect data, you need to have something to measure

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Measurement
To collect data, you need to have
something to measure
Measurement is the process of
assigning numbers or scores to
characteristics or attributes of the
objects or people people of
interest
Variables
• When we measure the attributes of an object, we
obtain a value that varies between objects.
• For example consider the people in this class as
objects and their height as the attribute
• The attribute height varies between objects, hence
attributes are more collectively known as variables
• Variables can be measured on four different scales
Attitudes
Expressions of inner feelings that reflect whether a
person is favorably or unfavorably predisposed to some
object -- a brand, a brand name, a service, a service
provider, a retail store, a company, an advertisement,
in essence, any marketing stimuli.
Opinions
A large amount of questions in marketing research are
designed to measure attitudes
Marketing managers want to understand consumers’
attitudes in order to influence their behavior
Three Components of Attitudes
The ABCs of attitudes:
 The Affective Component (based on feelings or
overall evaluation) Feelings of like or dislike
The Behavioral Component (likely action
toward object; e.g. from a consumer behavior
point of view, the consumer’s intention to buy a
product) Intentions to behave
The Cognitive Component (based on beliefs;
what you think about a marketing stimulus) –
Information possessed
Nominal Scale
Classifies data according to a
category only.
E.g., which color people select.
Colors differ qualitatively not
quantitatively.
A number could be assigned to
each color, but it would not have
any value.
The number serves only to
identify the color.
No assumptions are made that
any color has more or less value
than any other color.
Nominal Scale
 Assign subjects to groups or categories
– Mutually exclusive
– Collectively exhaustive
 No order or distance relationship
 No arithmetic origin
 Only count numbers in categories
 Only present percentages of categories
 Chi-square most often used test of statistical
significance
Other Examples
Sex
Social status
Marital status
Days of the week (months)
Geographic location
Patrons per hour
Ethnic Group
Types of restaurants
Brand choice
Religion
Job Type: Executive, Technical, Clerical
Coded as “1”
Coded as “2”
Nominal Scale
Which of the following media influences your purchasing
decisions the most?
–1 Television
–2 Radio
–3 Newspapers
–4 Magazines
Ordinal Scale
classifies nominal data
according to some order or rank
E.g. names ordered
alphabetically
With ordinal data, it is fair to
say that one response is greater
or less than another.
E.g. if people were asked to
rate the hotness of 3 chili
peppers, a scale of "hot",
"hotter" and "hottest" could be
used. Values of "1" for "hot",
"2" for "hotter" and "3" for
"hottest" could be assigned.
The gap between the
items is unspecified.
Ordinal Scale
Can include opinion
and preference scales
Median but not mean
No unique, arithmetic
origin
Means items cannot
be added
In marketing research
practice, ordinal scale
variables are often
treated as interval scale
variables
Ordinal Scale
Rank Player
Avg Points
Examples
1
Singh
13.58
2
Els
12.08
GPA
3
Woods
11.46
Small medium large
4
Mickelson
7.81
Quality
5
Goosen
7.08
6
Love-III
6.70
7
Weir
6.50
Likert scales, rank on a
scale of 1..5 your degree
of satisfaction
8
Harrington
6.09
9
Cink
5.33
10 Garcia
5.29
Women’s dress sizes
As at Oct 24 2004
Please rank the news programs offered in the following four
networks based on your preference.(1 for most preferred, 4
for least preferred).
_____ CTV
_____ Global
_____ A Channel
_____ CBC
Interval Scale
assumes that the measurements are made in
equal units.
i.e. gaps between whole numbers on the scale
are equal.
e.g. Fahrenheit and Celsius temperature scales
an interval scale does not have to have a true
zero. e.g. A temperature of "zero" does not mean
that there is no temperature...it is just an
arbitrary zero point.
Can’t perform full range of arithmetic
equations. 40 degrees is not twice as hot as 20
degrees
Permissible statistics: count/frequencies, mode,
median, mean, standard deviation
Interval Scale
How likely are you going to buy a new automobile within the
next six months? (Please check the most appropriate category)
Definitely will not buy
Probably will not buy
May or may not buy
Probably will buy
Definitely will buy
___
___
___
___
___
1
2
3
4
5
Ratio Scale
similar to interval scales except that
the ratio scale has a true zero value.
e.g. the time something takes
allows you to compare differences
between numbers.
Permits full arithmetic operation.
If a train journey takes 2 hr and 35
min, then this is half as long as a
journey which takes 5 hr and 10 min.
Ratio Scale
• Indicates actual amount of variable
– Shows magnitude of differences between points on scale
– Shows proportions of differences
• All statistical techniques useable
• Most powerful with most meaningful answers
• Allows comparisons of absolute magnitudes
Examples
height, weight, age,
Length
time
Income
7
Market share
6
5
4
3
2
1
0
1.What is your annual income
before taxes? $ _______
2. How far is your workplace
from home?
miles
_______
Primary Scales of Measurement
Nominal
Ordinal
Interval
Ratio
Numbers
Assigned to
Runners
4
81
9
Rank Order of
Winners
Performance
Rating on a 0 to
10 Scale
Time to Finish in
Seconds
Third
Place
Second
Place
First
Place
8.2
9.1
9.6
15.2
14.1
13.4
Comparison of Measurement Scales
Label Order Distance Origin
Nominal scale
Yes
No
No
No
Ordinal scale
Yes
Yes
No
No
Interval scale
Yes
Yes
Yes
No
Ratio scale
Yes
Yes
Yes
Yes
Use of Measurement Scales
• Nominal
– Used to categorize objects
• Ordinal
– Used to define ordered relationships
• Interval
– Used to rank objects such that the magnitude of the
difference between two objects can be determined
• Ratio
– Same as interval scale but has an absolute zero point
Always use the most powerful scale possible
Adding Sophistication To Scales
• Concept: Desire to watch Star Wars movies
– If a Star Wars movie is on television will you watch it?
• Yes _____ No _____
– How likely are you to watch a Star Wars movie shown
on television?
• Very Likely ____
Likely ____ Indifferent ___
• Unlikely _____ Very Unlikely _____
Another way to describe variables
• Qualitative variables: have a nominal scale of
measurement.
• Categorical variables: have a nominal or ordinal
scale of measurement.
• Quantitative variables: have an interval scale of
measurement.
• Continuous variables: have an Ordinal, interval,
or ratio variables scale of measurement.
Practice describing variables
• Q: What kind of variable is educational
attainment, and what scale is it measured in?
•A: Education is measured in number of years of
schooling, and is therefore a discrete quantitative
variable measured on an interval scale. (Or is it?)
•How could education be measure using…
–A nominal scale
–An ordinal scale
A Classification of Scaling Techniques
SCALING TECHNIQUES
Comparative
Scales
Paired
Comparison
Rank
Order
Constant
Sum
Non-Comparative
Scales
Others
Likert
Continuous
Rating
Scales
Semantic
Differential
Itemized
Rating
Scales
Stapel
Types of Scaling Techniques
 COMPARATIVE
SCALES
• Involve the respondent directly comparing stimulus objects.
• e.g. How does Pepsi compare with Coke on sweetness
 NON-COMPARATIVE
SCALES
• Respondent scales each stimulus object independently of
other objects
•e.g. How would you rate the sweetness of Pepsi on a scale of 1
to 10
Paired Comparison Items
If we have brands A, B, C and D, we would have
respondents compare
• A and B
• A and C
• A and D
• B and C
• B and D
• C and D
–Usually limited to N < 15
COMPARATIVE SCALES
Paired Comparison
Please indicate which of the following airlines you prefer
by circling your more preferred airline in each pair:
Air Canada
Air Transat
Zip
WestJet
Air Canada
Zip
WestJet
Air Canada
WestJet
Air Transat
Zip
Air Transat
COMPARATIVE SCALES
Constant Sum Scales
Allocate a total of 100 points among the following softdrinks depending on how favorable you feel toward each;
the more highly you think of each soft-drink, the more
points you should allocate to it. (Please check that the
allocated points add to 100.)
Coca-Cola
_____
points
7-Up
_____
points
Dr. Pepper
_____
points
Tab
_____
points
Pepsi-Cola
_____
points
100 points
Constant Sum Scale
Please divide 100 points among the following characteristics
so the division reflects the relative importance of each
characteristic to you in the selection of a bank
Hours of service
________________
Friendliness
_______________
Distance from home
________________
Investment vehicles
________________
Parking facilities
__________________
COMPARATIVE SCALES
Rank-Order Scales
Rank the following soft-drinks from 1 (best) to 5 (worst)
according to your taste preference:
Coca-Cola
_____
7-Up
_____
Dr. Pepper
_____
Pepsi-Cola
_____
Mountain Dew
_____
–Top and bottom rank choices are ‘easy’
–Middle ranks are usually most ‘difficult’
Comparative Scales
Rank Order Scale
Indicate your preferred type of music with a 1,
your second favorite with a 2, and so on for each
type of music:
____
____
____
____
____
Heavy Metal
Alternative
Urban Contemporary
Classical
Country
Instructions
Rank the various brands of toothpaste in order of preference. Begin by picking out
the one brand that you like most and assign it a number 1. Then find the second
most preferred- brand and assign it a number 2. Continue this procedure until you
have ranked all the brands of toothpaste in order of preference. The least
preferred brand should be assigned a rank of 10. No two brands should receive the
same rank number. The criterion of preference is entirely up to you. There is no
right or wrong answer. Just try to be consistent.
Brand
Rank Order
1. Crest
2. Colgate
3. Aim
4. Mentadent
5. Macleans
6. Ultra Brite
7. Close Up
8. Pepsodent
9. Plus White
10. Stripe
COMPARATIVE SCALES
Compared to Chevrolet, Ford is:
less
innovative
1
about the
same
2
3
4
more
innovative
5
6
7
Non comparative scale
Continuous scale
• How would you rate Marketing Research to
other courses this term
The worst
X
X
10 20 30 40 50 60 70 80 90 100
The Best
Itemized Rating Scales
Semantic
Differential
Scale
The Likert scale
Staple scale
Non-Comparative Scales
Non-Comparative Scales
Semantic Differential Scale
Here are a number of statements that could be used to describe
WalMart. For each statement tick ( X ) the box that best
describes your feelings about WalMart.
Modern Store
Old- fashioned store
Low prices
High prices
Unfriendly staff
Friendly staff
Narrow product range
Wide product range
Sophisticated customers
Unsophisticated customers
Semantic Differential Scale
Snake Diagram
X
Modern Store
Old- fashioned store
X
Low prices
X
Friendly staff
-
High prices
Unfriendly staff
Wide product range
X
Narrow product range
Sophisticated customers
X
Unsophisticated customers
Key :
Sears
X
WalMart
Itemised Rating Scales
Semantic differential
Old
X
Fashioned 1
Modern
2
3
4
2
3
X
4
2
X
3
Cheap
1
Friendly
service
1
4
5
Expensive
5
5
Unfriendly
service
Itemised Rating Scales
Likert scale
Cost is the
most
important
consideration
when buying a
new car
Strongly
agree
disagree
Neither
agree nor
disagree
agree
Strongly
agree
1
2
3
4
5
Itemised Rating Scales
The Likert scale
AGREEMENT
•Strongly Agree
•Agree
•Undecided
•Disagree
•Strongly Disagree
•Agree Very Strongly
•Agree Strongly
•Agree
•Disagree
•Disagree Strongly
•Disagree Very Strongly
•Agree Strongly
•Agree Moderately
•Agree Slightly
•Disagree Slightly
•Disagree Moderately
•Disagree Strongly
•Yes
•No
•Agree
•Disagree
•Agree
•Undecided
•Disagree
•Completely Agree
•Mostly Agree
•Slightly Agree
•Slightly Disagree
•Mostly Disagree
•Completely
Disagree
•Disagree Strongly
•Disagree
•Tend to Disagree
•Tend to Agree
•Agree
•Agree Strongly
FREQUENCY
•Very Frequently
•Frequently
•Occasionally
•Rarely
•Very Rarely
•Never
•Always
•Very Frequently
•Occasionally
•Rarely
•Very Rarely
•Never
•Always
•Usually
•About Half the Time
•Seldom
•Never
•A Great Deal
•Much
•Somewhat
•Little
•Never
•Often
•Sometimes
•Seldom
•Never
•Always
•Very Often
•Sometimes
•Rarely
•Never
•Almost Always
•To a Considerable Degree
•Occasionally
•Seldom
IMPORTANCE
•Very Important
•Important
•Moderately Important
•Of Little Importance
•Unimportant
•Very Important
•Moderately Important
•Unimportant
QUALITY
•Very Good
•Good
•Barely Acceptable
•Poor
•Very Poor
•Extremely Poor
•Below Average
•Average
•Above Average
•Excellent
•Good
•Fair
•Poor
LIKELIHOOD
•Like Me
•Unlike Me
•To a Great Extent
•Somewhat
•Very Little
•Not at All
•True
•False
•Definitely
•Very Probably
•Probably
•Possibly
•Probably Not
•Very Probably Not
•Almost Always True
•Usually True
•Often True
•Occasionally True
•Sometimes But Infrequently True
•Usually Not True
•Almost Never True
•True of Myself
•Mostly True of Myself
•About Halfway True of Myself
•Slightly True Of Myself
•Not at All True of Myself
Itemised Rating Scales
Staple scale
+5
+5
+4
+4
+3
+3
+2
+2
+1
+1
High quality
Poor service
-1
-1
-2
-2
-3
-3
-4
-4
-5
-5
A Stapel Scale for Measuring a Store’s Image
Select a plus number for words that
you think describe the store
accurately. The more accurately you
think the work describes the store,
the larger the plus number you
should choose. Select a minus
number for words you think do not
describe the store accurately. The
less accurately you think the word
describes the store, the larger the
minus number you should choose,
therefore, you can select any number
from +3 for words that you think are
very accurate all the way to -3 for
words that you think are very
inaccurate.
WalMart
+5
+5
+5
+4
+4
+4
+3
+3
+3
+2
+2
+2
+1
+1
+1
High Poor Wide
Quality Service Variety
-1
-1
-1
-2
-2
-2
-3
-3
-3
-4
-4
-4
-5
-5
-5
Staple Scale
The following questions concern your ratings of several
suppliers that provide products for use in your store.
XYZ
Poor Product
Selection
-5
-4
-3
-2
-1
1
2
3
4
5
Costly Products
-5
-4
-3
-2
-1
1
2
3
4
5
Fast Service
-5
-4
-3
-2
-1
1
2
3
4
5
High Quality
Products
-5
-4
-3
-2
-1
1
2
3
4
5
Innovative
-5
-4
-3
-2
-1
1
2
3
4
5
Some Basic Considerations
When Selecting a Scale
Selecting a Rating, Ranking,
Sorting, or Purchase Intent
Scale
Number of Categories
Forced Versus Non-forced
Choice
Odd or Even Number of
Scale Categories
Balanced Versus Nonbalanced Alternatives
Odd versus even
if neutral responses likely, use odd number
Odd
Even
Strongly Agree
_____ Strongly Agree_____
Agree
_____ Agree
_____
Neutral
_____ Disagree
_____
Disagree
_____ Strongly disagree___
Strongly disagree_____
Balanced vs. Unbalanced
Balanced
Unbalanced
Very good
______
Excellent
______
Good
______
Very Good
______
Fair
______
Good
______
Poor
______
Fair
______
Very Poor
______
Poor
______
Balanced and Unbalanced Scales
Balanced Scale
Unbalanced Scale
JOVAN MUSK FOR MEN IS
JOVAN MUSK FOR MEN IS
Extremely good
Very good
Good
Bad
Very bad
Extremely bad
Extremely good
Very good
Somewhat Good
Good
Bad
Very bad
Forced vs. Unforced
Unforced
Forced
Extremely Reliable
___
Extremely Reliable
___
Very Reliable
___
Very Reliable
___
Somewhat Reliable
___
Somewhat Reliable
___
Somewhat Unreliable ___
Somewhat Unreliable ___
Very Unreliable
___
Very Unreliable
___
Extremely Unreliable
___
Extremely Unreliable
___
Don’t know
___
Labeled vs. End Anchored
Labeled
End Anchored
Excellent
_____
Very Good
_____
_____
_____
Fair
_____
_____
Poor
_____
_____
Very Poor
_____
Excellent
Poor
_____
Intervals May Not Reflect the Semantic
Meaning of the Adjectives
Excellent _____
Labeled
Intervals Are
Not Equal
Excellent
_____
Very Good
_____
Very Good_____
Fair
_____
Fair
_____
Poor
_____
Poor
_____
Very Poor
_____
Intervals Are
Not Equal
Very Poor _____
Number of Scale Points
5 Point
Excellent
10 Point
_____
Excellent
_____
_____________
_____
_____________
_____________
_____________
_____
_____________
_____________
_____
Poor
_____
_____________
_____________
Poor
_____________
Choosing the Appropriate Scale
Attitude
component
Itemized
category
Rank Constant
order sum
Likert
Semantic
differential
A
Knowledge
Awareness
A
Attribute beliefs
A
B
B
B
Attribute
importance
A
B
A
B
Overall
preferences
A
B
A
B
B
Specific
attributes
A
B
B
B
A
A
B
A
B
Affect or Liking
Action
intentions
A = Very appropriate, B = Sometimes appropriate
Characteristics of Good
Measurement Scales
1. Reliability
• The degree to which a measure accurately captures an
individual’s true outcome without error; Accuracy
• synonymous with repetitive consistency
2. Validity
• The degree to which a measure faithfully represents the
underlying concept; Fidelity (it asks the right questions)
3. Sensitivity
• The ability to discriminate meaningful differences
between attitudes. The more categories the more sensitive
(but less reliable)
4. Generalizability
• How easy is scale to administer and interpret
Validity and Reliability
If a measure is valid, then it is reliable
If it is not reliable, it can not be valid
If it is reliable, it may or may not be valid
Reliability can be more easily determined than
validity
Reliability and Validity
Neither Reliable
Nor Valid
Reliable But
Not Valid
Reliable
And Valid
Example of low validity, high
reliability
• Scale is perfectly accurate, but is capturing the
wrong thing; for example, it measures
consumers’ interest in creative writing rather
than preference for kinds of stationery.
Example of modest validity, low
reliability
• Scale genuinely measures consumers’
interest in kinds of stationery, but poorly
worded items, sloppy administration, data
entry errors lead to random errors in data
• Note that reliability sets an upper limit on
validity -- a measure with a lot of errors is
limited in how well it can capture a concept
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