Business Research Methods

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Business Research Methods

• Chapter 13
• Measurement

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CONCEPT

• A GENERALIZED IDEA ABOUT A CLASS OF OBJECTS,
  ATTRIBUTES, OCCURRENCES, OR PROCESSES.
• Age, gender, number of children.
• Or
• Brand loyalty, Power, Job involvement etc.

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OPERATIONAL DEFINITION

• Specifies what the researcher must do to measure
  the concept under investigation
• E.g., Brand loyalty is the percentage of times a
  person buys a specific brand in a given period of
  time.
• Or
• Measure Attitudes towards a brand.

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SCALES

• Nominal
• Ordinal
• Interval
• Ratio

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NOMINAL SCALE PROPERTIES

• UNIQUELY CLASSIFIES
• Sammy Sosa 21
• Mark McGwire 25

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NOMINAL SCALE PROPERTIES

• Classification - gender, class in school etc.
• Mode, frequencies - number and percentage

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ORDINAL SCALE PROPERTIES

• UNIQUELY CLASSIFIES
• PRESERVES ORDER
• WIN, PLACE SHOW

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ORDINAL SCALE PROPERTIES

• Rankings/preferences.
• Frequencies, Median, Range, Percentile Ranking.

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INTERVAL SCALE PROPERTIES

• UNIQUELY CLASSIFIES
• PRESERVES ORDER
• EQUAL INTERVALS
• CONSUMER PRICE INDEX
• (BASE 100)
• FAHRENHEIT
• TEMPERATURE

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INTERVAL SCALE PROPERTIES

• Agree/disagree
• Frequencies, Median, Range, Percentile Ranking.
• Mean, S.D., Variance, Correlations.,
• T-Tests, F-tests.

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RATIO SCALE PROPERTIES

• UNIQUELY CLASSIFIES
• PRESERVES ORDER
• EQUAL INTERVALS
• NATURAL ZERO
• WEIGHT AND DISTANCE

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RATIO SCALE PROPERTIES

• All arithmetic operations possible.
• Frequencies, Median, Range, Percentile Ranking.
• Mean, S.D., Variance, Correlations.,
• T-Tests, F-tests.
• Geometric mean, Coefficient of variation.

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THE GOAL OF MEASUREMENT VALIDITY
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Validity

• The ability of a scale to measure what was
  intended to be measured.

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Reliability

• The degree to which measures are free from random
  error and therefore yield consistent results.

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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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VALIDITY
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Face or Content validity.

• Degree to which the instrument items represent
  the universe of the concept under study.
• Define the concept precisely.
• Conduct an exhaustive literature search and run
  focus groups.

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Criterion validity.

• The degree to which a measurement instrument can
  predict a variable that is designated a
  criterion.
• Predictive and concurrent validity.

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Construct Validity.

• The degree to which a measurement instrument
  represents and logically connects, via the
  underlying theory, the observed phenomenon to the
  construct.
• Convergent and discriminant validity.

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RELIABILITY
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Test-retest reliability.

• Test-retest reliability - use the same instrument
  a second time under as similar conditions as
  possible.
• Difficult to locate and gain cooperation of
  respondents, first measurement could alter
  second, environmental or personal change could
  occur.

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Equivalent Forms Reliability.

• Equivalent forms - Use two instruments that are
  as similar as possible to measure the same object
  during the same time period.
• Difficult to create two equivalent forms, time
  consuming and expensive.

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Split Half/Internal Consistency.

• Compare different sample of items being used to
  measure a phenomenon during the same time period.
• Split-half - dividing into the total set of items
  and correlating the results.
• Internal Consistency- Cronbachs-Alpha - computes
  the mean reliability coefficient estimates for
  all possible ways of splitting a set of items in
  half.