King Fahd University of Petroleum & Minerals
Department of Management and Marketing
MKT 345 Marketing Research
Dr. Alhassan G. Abdul-Muhmin
Measuring Attitudes and Other
Psychological Constructs
Reference: Zikmund, Chapter 14
Learning Objectives
•
At the end of the discussion you should be able to:
1. Identify and describe the basic approaches to
measuring attitudes and other psychological
constructs
2. Identify and describe the characteristics of different
types of ratings scales used in measuring attitudes
and other constructs
3. Discuss the major issues to be addressed in choice
of rating scales
Some Approaches to Measuring Hypothetical Constructs
(e.g. Attitudes)
Following are approaches that have been used to measure psychological
constructs:
Physiological Measures, e.g.:
1.
–
–
–
–
Galvanic skin response (Galvanometer).
Pupil dilations (Pupilometer).
Eye Movement (Eye-tracking equipment).
Voice-pitch levels.
2.
Observation of overt behavior.
3.
4.
Indirect (Projective) techniques.
Subjects’ self-reports
a) Choice
b) Ranking
c) Sorting
d) Rating
•
•
Attitude rating scales
Selecting a measurement scale
Rating Scales
Measurement scales that allow a respondent to
register the degree (or amount) of a characteristic or
attribute possessed by an object directly on the scale.
Six main types of rating scales:
1.
2.
3.
4.
5.
6.
Category scale
Semantic differential scale
Stapel scale
Likert scale (Summated ratings scale)
Constant sum scale
Graphic scale
Category Scale
•
A rating scale which the response options provided for a
closed-ended question are labeled with specific verbal
descriptions.
Example:
Please rate car model A on each of the following dimensions:
a)Durability
b)Fuel consumption
Poor
[ ]
[ ]
Fair
[ ]
[ ]
Good
[
]
[
]
V.good
[
]
[
]
Excellent
[
]
[
]
Characteristics:
•
Response options are still verbal descriptions.
•
Response categories are usually ordered according to a particular descriptive or
evaluative dimension.
•
Therefore scale has ordinal properties.
•
However, researchers often assume that it possesses interval properties => but
this is only an assumption.
** One special version is the Simple category scale.
Simple Category Scale
• A category scale with only two response categories
(or scale points) both of which are labeled.
Example:
Please rate brand A on each of the following
dimensions:
poor
excellent
a) Durability
[ ]
[
]
b) Fuel consumption [ ]
[
]
Semantic Differential Scale
•
A rating scale in which bipolar adjectives are placed at both
ends (or poles) of the scale, and response options are
expressed as “semantic” space.
Example:
Please rate car model A on each of the following dimensions:
Durable
Low fuel consumption
---:-X-:---:---:---:---:--- Not durable
---:---:---:---:---:-X-:--- High fuel consumption
Characteristics
1. The scale has properties of an interval scale.
2. Sometimes descriptive phrases are used instead of bipolar
adjectives, especially when it is difficult to get adjectives that
are exact opposites
3. It is often used to construct an image profile.
Stapel Scale
•
A simplified version of the semantic differential scale in which a
single adjective or descriptive phrase is used instead of bipolar
adjectives.
Characteristics
1.
The scale measures both the direction and intensity of the attribute
simultaneously.
2.
It has properties similar to the semantic differential.
Example:
Model A
-3 -2 -1
Durable Car
1 2 3
-3 -2 -1 Good Fuel Conaumption 1 2 3
Constant-Sum Scale
•
•
A rating scale in which respondents divide a constant sum
among different attributes of an object (usually to indicate
the relative importance of each attribute).
Assumed to have ratio level properties.
Example: Divide 100 points among the following dimensions to
indicate their level of importance to you when you purchase
a car:
Durability
Fuel Consumption
Total
100
Numerical Scale
• Any rating scale in which numbers rather than semantic
space or verbal descriptions are used as response
options.
Examples:
Poor
Durability 1 2
Durable
1
2
3
3
4
4
5
5
6
Excellent
6
7
7 Not durable
Graphic Ratings Scales
•
•
Rating scales in which respondents rate an object on
a graphic continuum, usually a straight line.
Modified versions are the ladder scale and happy
face scale.
Characteristics
1. The straight line scale has ratio level properties.
2. The ladder and happy face scales have properties
depending on the labeling option chosen – whether
all response categories are labeled (ordinal
properties) or only the scale end-points are labeled
(interval properties).
The Likert Scale (Summated Ratings Scale)
• A multiple item rating scale in which the degree of an attribute
possessed by an object is determined by asking respondents to
agree or disagree with a series of positive and/or negative
statements describing the object.
• Example:
Attitude toward buying from the Internet
Totally
disagree Disagree Neutral
a) Shopping takes much longer on the Internet
[ ]
[ ]
[ ]
b) It is a good thing that Saudi consumers have
the opportunity to buy products through the
[ ]
[ ]
[ ]
c) Buying products over the Internet is not a
sensible thing to do
[ ]
[ ]
[ ]
Agree
[ ]
Totally
agree
[ ]
[ ]
[ ]
[ ]
[ ]
Characteristics of the Likert Scale
•
1.
2.
3.
4.
•
The following procedure is used to analyze data from Likert
scales:
First, weights are assigned to the responses options, e.g. Totally
agree=1, Agree=2, etc
Then negatively-worded statements are reverse-coded (or reverse
scored). E.g. a score of 2 for a negatively-worded statement with a
5-point response options is equivalent to a score of 4 on an
equivalent positive statement.
Next, scores are summed across statements to arrive at a total (or
summated) score.
Each respondent’s score can then be compared with the mean
score or the scores of other respondents to determine his level of
attitude, loyalty, or other construct that is being measured
Note that the response for each individual statement is expressed
on a category scale.
Characteristics Different Types of Rating Scales
Subject must:
Advantages
Disadvantages
2.Category scale
Indicate a response
category
Flexible, easy to respond
Ambiguous items, few
categories, only gross
distinction.
3. Likert scale
Evaluate statements on a
5-point scale
Easiest scale to construct
Hard to judge what a
single score means
4. Semantic differential
and numerical scales
Choose points between
bipolar adjectives on
relative dimensions
Easy to construct, norms
exist for comparison, e.g.
profile analysis
Bipolar adjectives must be
found, data may be
ordinal, not interval
5. Constant sum scale
Divide a construct sum
among response
alternatives
Scale approximates an
interval measure
Difficult for respondents
with low education levels
6. Stapel scale
Choose point on scale
with 1 center adjective
Easier to construct than
semantic differential
Endpoints are numerical,
not verbal.
7. Graphic scale
Choose a point on a
continuum
Visual impact, unlimited
scale points
No standard answers
8. Graphic scale-picture
response
Choose a visual picture
Visual impact, easy for
poor readers
Hard to attach a verbal
explanation to response
Rating Scale
1. Simple attitude scaling
Issues In Selecting A Measurement Scale
1.
2.
3.
Whether to use single or index measure.
Whether to use a ranking, sorting, choice, or rating scale.
Whether to use monadic or comparative scale.
•
•
•
4.
5.
Monadic rating scale is one in which respondents evaluate an object
in isolation
Comparative scale s one in which the object is evaluated in relation
to other objects
Construction and labeling is different for monadic and comparative
scales
Whether to use category labels or not.
If the decision is to use category labels, what labels to use.
Issues In Selecting A Measurement Scale
6.
Number of response options (scale categories) to use, i.e
whether to use 2, 3, 4, 5, etc response categories
•
7.
In general, the larger the number of categories the more sensitive the
scale is; but also the more difficult it is for respondents to answer
Whether to use balanced or unbalanced scale.
•
A balanced scale has an equal number of points to the left and right of
a mid-point. An unbalanced scale has more response options on one
side than the other
8. Whether the scale should force choice among the response
categories, i.e should the scale contain a “neutral” or “don’t
know” category.