King Fahd University of Petroleum

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King Fahd University of Petroleum
MineralsDepartment of Management and
MarketingMKT 345 Marketing ResearchDr.
Alhassan G. Abdul-Muhmin

• Measuring Attitudes and Other Psychological
  Constructs Reference Zikmund, Chapter 14

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Learning Objectives

• At the end of the discussion you should be able
  to
• Identify and describe the basic approaches to
  measuring attitudes and other psychological
  constructs
• Identify and describe the characteristics of
  different types of ratings scales used in
  measuring attitudes and other constructs
• Discuss the major issues to be addressed in
  choice of rating scales

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Some Approaches to Measuring Hypothetical
Constructs (e.g. Attitudes)

• Following are approaches that have been used to
  measure psychological constructs
• Physiological Measures, e.g.
• Galvanic skin response (Galvanometer).
• Pupil dilations (Pupilometer).
• Eye Movement (Eye-tracking equipment).
• Voice-pitch levels.
• Observation of overt behavior.
• Indirect (Projective) techniques.
• Subjects self-reports
• Choice
• Ranking
• Sorting
• Rating
• Attitude rating scales
• Selecting a measurement scale

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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
• Category scale
• Semantic differential scale
• Stapel scale
• Likert scale (Summated ratings scale)
• Constant sum scale
• Graphic scale

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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
• Poor Fair Good V.good Excellent
• a)Durability
  
• b)Fuel consumption
  
• 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 gt but this is only
  an assumption.
• One special version is the Simple category
  scale.

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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

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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 ----X---------------- Not
  durable
• Low fuel consumption ----------------X----
  High fuel consumption
• Characteristics
• The scale has properties of an interval scale.
• Sometimes descriptive phrases are used instead of
  bipolar adjectives, especially when it is
  difficult to get adjectives that are exact
  opposites
• It is often used to construct an image profile.

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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
• The scale measures both the direction and
  intensity of the attribute simultaneously.
• It has properties similar to the semantic
  differential.
• Example

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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

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Numerical Scale

• Any rating scale in which numbers rather than
  semantic space or verbal descriptions are used as
  response options.
• Examples
• Poor Excellent
• Durability 1 2 3 4 5 6 7
• Durable 1 2 3 4 5 6
  7 Not durable

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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
• The straight line scale has ratio level
  properties.
• 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).

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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

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Characteristics of the Likert Scale

• The following procedure is used to analyze data
  from Likert scales
• First, weights are assigned to the responses
  options, e.g. Totally agree1, Agree2, 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 respondents 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.

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Characteristics Different Types of Rating Scales
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Issues In Selecting A Measurement Scale

• Whether to use single or index measure.
• Whether to use a ranking, sorting, choice, or
  rating scale.
• Whether to use monadic or comparative scale.
• 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.

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Issues In Selecting A Measurement Scale

• Number of response options (scale categories) to
  use, i.e whether to use 2, 3, 4, 5, etc response
  categories
• 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
• Whether the scale should force choice among the
  response categories, i.e should the scale contain
  a neutral or dont know category.