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Ethics in Marketing Research

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					Comparative Scaling
             Some Key Concepts
• Measurement
  – Assigning numbers or other symbols to characteristics
    of objects being measured, according to
    predetermined rules.
• Concept (or Construct)
  – A generalized idea about a class of objects, attributes,
    occurrences, or processes.
     • Relatively concrete constructs
        – Age, gender, number of children, education, income
     • Relatively abstract constructs
        – Brand loyalty, personality, channel power, satisfaction
            Some Key Concepts
• Scaling
  – The generation of a continuum upon which measured
    objects are located.
• Scale
  – A quantifying measure – a combination of items that
    is progressively arranged according to value or
    magnitude.
  – Purpose is to quantitatively represent an item’s,
    person’s, or event’s place in the scaling continuum.
Primary Scales of Measurement

                    Primary
                     Scales




Nominal
 Scale                                   Ratio
                                         Scale

          Ordinal
           Scale              Interval
                               Scale
 Primary Scales of Measurement
• Nominal
  – A scale in which the numbers or letters
    assigned to objects serve as labels for
    identification or classification.
• Ordinal
  – A scale that arranges objects or
    alternatives according to their magnitude
    in an ordered relationship.
  Primary Scales of Measurement
• Interval
  – A scale that both arranges objects
    according to their magnitudes and
  – Distinguishes the ordered arrangement in
    units of equal intervals
  – I.e., indicate order and measure order (or
    distance) in units of equal intervals
 Primary Scales of Measurement
• Ratio
  –A scale that has absolute rather than
   relative quantities and an absolute
   zero where a given attribute is absent.
  –Money & weight are good examples
   of attributes that possess absolute
   zeros and interval properties.
     Primary Scales of Measurement
Scale

Nominal    Numbers
           Assigned             1      31       88
           to Drivers/Cars


Ordinal    Rank Order          Third   Second   First
           of race finishers   Place   Place    Place



Interval   Championship
           Points earned        170    175       185


Ratio      Time to Finish,
           behind winner         5.1    2.3       0.0
  Classifying Scaling Techniques
• Comparative Scales
 –Involve the direct comparison of
  two or more objects
• Noncomparative Scales
 –Objects or stimuli are scaled
  independently of each other.
    Classifying Scaling Techniques
                             Scaling
                           Techniques


         Comparative                      Noncomparative
           Scales                             Scales



                                   Continuous           Itemized
  Paired               Constant    Rating Scales      Rating Scales
Comparison               Sum
             Rank
             Order
                                        Likert
                                                                Stapel
                                                 Semantic
                                                 Differential
     Paired Comparison Scaling
• Respondent is presented with two objects at a
  time
• Then asked to select one object in the pair
  according to some criterion
• Data obtained are ordinal in nature
  – Arranged or ranked in order of magnitude
• Easy to do if only a few items are compared.
• If number of comparisons is too large,
  respondents may become fatigued and no longer
  carefully discriminate among them.
 Paired Comparison Scaling: Example
For each pair of professors, please indicate the professor from whom
you prefer to take classes with a 1.

              Cunningham         Day         Parker        Thomas


Cunningham                        0             0             0


Day                 1                           1             0

Parker              1             0                           0

Thomas              1             1             1             0

# of times
                   3              1             2             0
preferred
         Rank Order Scaling
• Respondents are presented with several
  objects simultaneously
• Then asked to order or rank them
  according to some criterion.
• Data obtained are ordinal in nature
  – Arranged or ranked in order of magnitude
• Commonly used to measure preferences
  among brands and brand attributes
                 Rank Order Scaling
Please rank the instructors listed below in order of preference. For the
instructor you prefer the most, assign a “1”, assign a “2” to the instructor
you prefer the 2nd most, assign a “3” to the instructor that you prefer 3rd
most, and assign a “4” to the instructor that you prefer the least.

     Instructor                                  Ranking

     Cunningham                                       1

     Day                                              3

     Parker                                           2

     Thomas                                           4
        Constant Sum Scaling
• Respondents are asked to allocate a constant
  sum of units among a set of stimulus objects
  with respect to some criterion
• Units allocated represent the importance
  attached to the objects.
• Data obtained are interval in nature
• Allows for fine discrimination among
  alternatives
                 Constant Sum Scaling
Listed below are 4 marketing professors, as well as 3 aspects that students
typically find important. For each aspect, please assign a number that reflects how
well you believe each instructor performs on the aspect. Higher numbers
represent higher scores. The total of all the instructors’ scores on an aspect should
equal 100.

  Instructor             Availability          Fairness            Easy Tests

  Cunningham                  30                   35                   25

  Day                         30                   25                   25

  Parker                      25                   25                   25

  Thomas                      15                   15                   25

  Sum Total                   100                 100                  100
Non-Comparative Scaling
Classifying Noncomparative Scaling Techniques

                      Noncomparative
                       Rating Scales


    Continuous                              Itemized
   Rating Scales                          Rating Scales




             Semantic
                                 Stapel             Likert
            Differential
          Continuous Rating Scale
                 Example


Very                                                    Very
                   X
Poor                                                    Good
     0   10   20   30   40   50   60   70   80   90   100
     Method of Summated Ratings:
          The Likert Scale
• Extremely popular means for measuring
  attitudes.
• Respondents indicate their own attitudes by
  checking how strongly they agree/disagree
  with statements.
• Response alternatives:
  – “strongly agree”, “agree”, “uncertain”,
    “disagree”, and “strongly disagree”.
• Generally use either a 5- or 7-point scale
      Semantic Differential Scales
• A series of numbered (usually seven-point)
  bipolar rating scales.
• Bipolar adjectives (for example, “good”
  and “bad”), anchor both ends (or poles) of
  the scale.
• A weight is assigned to each position on the
  rating scale.
  – Traditionally, scores are 7, 6, 5, 4, 3, 2, 1, or
    +3, +2, +1, 0, -1, -2, -3.
  Semantic Differential Scales for
 Measuring Attitudes Toward Tennis

Exciting ___ : ___ : ___ : ___ : ___ : ___ : ___ : Calm

Interesting ___ : ___ : ___ : ___ : ___ : ___ : ___ : Dull

Simple___ : ___ : ___ : ___ : ___ : ___ : ___ Complex

Passive ___ : ___ : ___ : ___ : ___ : ___ : ___ Active
                Stapel Scales
• Modern versions of the Stapel scale place a
  single adjective as a substitute for the
  semantic differential when it is difficult to
  create pairs of bipolar adjectives.
• The advantage and disadvantages of a Stapel
  scale, as well as the results, are very similar
  to those for a semantic differential.
• However, the Stapel scale tends to be easier
  to conduct and administer.
          A Stapel Scale
   for Measuring a Store’s Image
                 Department
                 Store Name
                     +3
                     +2
                     +1
Wide Selection
                     -1
                     -2
                     -3
         Graphic Rating Scales

   A graphic rating scale presents respondents
    with a graphic continuum.
 Graphic Rating Scale Stressing
Pictorial Visual Communications




      3        2        1
     Very              Very
     Good              Poor
Balanced and Unbalanced Scales

   Balanced Scale           Unbalanced Scale
 Surfing the Internet is   Surfing the Internet is
____ Extremely Good        ____ Extremely Good
____ Very Good             ____ Very Good
____ Good                  ____ Good
____ Bad                   ____ Somewhat Good
____ Very Bad              ____ Bad
____ Extremely Bad         ____ Very Bad
               Summary of Itemized Rating Scale Decisions


1. Number of categories      While there is no single, optimal number, traditional guidelines
                             suggest that there should be between five and nine categories.


2. Balanced vs. unbalanced   In general, the scale should be balanced to obtain objective data.


3. Odd or even number of     If a neutral or indifferent scale response is possible for
 categories                  at least some of the respondents, an odd number of categories
                             should be used.
Summary of Itemized Rating Scale Decisions (continued)


4. Forced versus nonforced   In situations where the respondents are expected

                             to have no opinion, the accuracy of data may be
                             improved by a nonforced scale.


5. Verbal description        An argument can be made for labeling all or many
                             scale categories. The category descriptions should

                             be located as close to the response categories as
                             possible.



6. Physical form             A number of options should be tried and the best

                             one selected.
   Scale Evaluation
                            Scale
                          Evaluation
                                               Validity
         Reliability


                                  Content
Test-Retest
                    Internal                 Criterion
                   Consistency
    Alternative
      Forms                                               Construct
                                  Convergent
                                   Validity
                                       Discriminant
                                         Validity   Nomological
                                                      Validity
                    Reliability
• Extent to which a scale produces consistent
  results
• Test-retest Reliability
  – Respondents are administered scales at 2 different
    times under nearly equivalent conditions
• Alternative-form Reliability
  – 2 equivalent forms of a scale are constructed, then
    tested with the same respondents at 2 different times
                      Reliability
• Internal Consistency Reliability
  – The consistency with which each item represents the
    construct of interest
  – Used to assess the reliability of a summated scale
  – Split-half Reliability
     • Items constituting the scale divided into 2 halves, and
       resulting half scores are correlated
  – Coefficient alpha (most common test of reliability)
     • Average of all possible split-half coefficients resulting
       from different splittings of the scale items
                           Validity
• Extent to which true differences among the objects are
  reflected on the characteristic being measured
• Content Validity
   – A.k.a., face validity
   – Subjective, but systematic evaluation of the representativeness
     of the content of a scale for the measuring task at hand
• Criterion Validity
   – Examines whether measurement scale performs as expected in
     relation to other variables selected as meaningful criteria
   – I.e., predicted and actual behavior should be similar
                Construct Validity
• Addresses the question of what construct or
  characteristic the scale is actually measuring
• Convergent Validity
   – Extent to which scale correlates positively with other measures
     of the same construct
• Discriminant Validity
   – Extent to which a measure does not correlate with other
     constructs from which it is supposed to differ
• Nomological Validity
   – Extent to which scale correlates in theoretically predicted
     ways with measures of different but related constructs
Relationship Between Reliability and
              Validity
• A scale can be reliable, but not valid
• In order for a scale to valid, it must
  also be reliable.
• In other words,
  –Reliability is a necessary but
   insufficient condition for Validity.
 Reliability and Validity on Target




  Old Rifle         New Rifle        New Rifle Sunglare
Low Reliability   High Reliability    Reliable but Not
                                           Valid
  (Target A)        (Target B)          (Target C)

				
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