2. Outline
• An Overview of Measurement
• Constructs and Operational Definitions
• Validity and Reliability of Measurement
• Scales of Measurement
• Modalities of Measurement
• Other Aspects of Measurement
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3. An Overview Of Measurement
• The research process
– Find an unanswer question
– Forming a hypothesis
– Developing a research study
– Defining and measuring the variables
• Variables : characteristics or conditions
that change or have different values for
different individuals
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4. Aspects of measurement
• Not a one to one relationship
– Variable being measured : Measurements
obtained
• Usually several different options for measuring
particular variable
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5. Example
Measure Knowledge for each student
Impossible to look inside each student’ head
An An
exam essay
A set of
problems
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6. The selection of a measurement
procedure
• The general process of measurement
• The different measurement options
• The consequences of each option
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8. Constructs Definitions
• Hypothetical attributes or mechanisms
that help explain and predict behavior in a
theory
External External
Constructs
Stimulus behavior
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9. Operational Definitions
• A procedure for measuring and defining a
construct
Definition and Measurement of
Definition and Measurement of
the hypothetical construct
the hypothetical construct
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12. Outline
• An Overview of Measurement
• Constructs and Operational Definitions
• Validity and Reliability of Measurement
• Scales of Measurement
• Modalities of Measurement
• Other Aspects of Measurement
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13. Validity and Reliability of
Measurement
• Validity of Measurement
• Definitions of Validity
• Reliability of Measurement
– Type and Measures of Reliability
• The Relationship Between Reliability
and Validity
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14. Validity of Measurement
• Validity : first criterion for evaluation a
measurement procedure
• Definition
– The validity of a measurement procedure
is the degree to which the measurement
process measures the variable that it
claims to measure.
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15. Methods for Assessing the Validity
of Measurement
• Face Validity
• Concurrent Validity
• Consistency of a Relationship
• Predictive Validity
• Construct Validity
• Convergent and Divergent Validity
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16. Face Validity
• Definition of Face Validity : Simplest and
least scientific
• Concerns the superficial appearance
IQ
Test
Logic, reasoning, background knowledge, good memory
Intelligence
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17. Concurrent Validity
• The scores obtained from the new
measurement technique are directly
related to the scores obtained from
another
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18. Consistency of a Relationship
• The validity (and reliability) of measurement
a can be established by demonstrating the
consistency of a relationship between two
different measurements
Test of IQ
Test of IQ
Score from a STANDARDIZE IQ test
Relationship
Score from a NEW IQ test
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19. Scatter Plots Showing Different Relationships
Positive Relationship Negative Relationship
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20. Predictive Validity
• Theories predict how difference values
of a construct affect behavior
• The measurement of a construct
accurately predict according to the
theory
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21. Construct Validity
• The demonstrate that measurements of
a specific variable behave in exactly
the same way as the past research
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22. Convergent and Divergent Validity
• Convergent Validity is demonstrated by a
strong relationship between the scores
obtains from two difference methods of
measuring the same construct
• Divergent Validity is demonstrated by
using two different methods to measure two
different constructs. Then there should be
little or no relationship between the scores
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23. Validity and Reliability of
Measurement
• Validity of Measurement
• Definitions of Validity
• Reliability of Measurement
– Type and Measures of Reliability
• The Relationship Between Reliability
and Validity
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24. Reliability of Measurement
• The second criterion for evaluating the
quality of a measurement procedure
• Reliability : Repeatedly to measure the
same individual under the same condition,
should nearly
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25. Concept of Reliability
Should
average
to ZERO
Measured Score = True Score + Error
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26. Sources of Error
• Observer Error
• Environment Error
• Participant Error
example Test of intelligence
IQ test
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27. Type and Measures of Reliability
• Successive measurement
• Simultaneous measurement
• Internal consistency
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28. Type and Measures of Reliability
• Successive measurement
• A researcher may use exactly the same
measurement procedure for the same group of
individuals at two different times
• Called Test - Retest reliability
• Simultaneous measurement
• Measurements are obtained by direct observation
of behaviors, it is common to use two or more
separate observers who simultaneously record
measurement
• Called inter-rater reliability
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29. Type and Measures of Reliability
• Successive measurement
• Simultaneous measurement
• Internal consistency
• General process results : Split-half reliability
Example :
1. Use multiple-exams to measure performance in
an academic course
2. Splitting the exams in half
3. Then calculating the degree of consistency
between the two scores for a group of participants
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30. The Relationship Between Reliability
and Validity
• Both : Criteria for evaluation the quality
measurement procedure
• Partially related and Partially independent
– Related : Reliability is a prerequisite for
validity
– independent : Not necessary for a
measure to be valid for to be reliable
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31. Outline
• An Overview of Measurement
• Constructs and Operational Definitions
• Validity and Reliability of Measurement
• Scales of Measurement
• Modalities of Measurement
• Other Aspects of Measurement
To be Continue
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