2. Part Two THE DESIGN OF RESEARCH
McGraw-Hill/Irwin
© 2003 The McGraw-Hill Companies, Inc.,All Rights Reserved.

3. Chapter Eight MEASUREMENT

4. Measurement Selecting observable empirical events
Using numbers or symbols to represent aspects of the events
Applying a mapping rule to connect the observation to the symbol

5. What is Measured? Objects: Properties: characteristics of objects
Things of ordinary experience
Some things not concrete
Properties: characteristics of objects

6. Characteristics of Data
Classification
Order
Distance (interval between numbers)
Origin of number series

7. Data Types Order Interval Origin Nominal none none none
Ordinal yes unequal none
Interval yes equal or none
unequal
Ratio yes equal zero

8. Sources of Measurement Differences
Respondent
Situational factors
Measurer or researcher
Data collection instrument

9. Validity Content Validity Criterion-Related Validity
Predictive
Concurrent
Construct Validity

10. Reliability Stability Equivalence Internal Consistency Test-retest
Parallel forms
Internal Consistency
Split-half
KR20
Cronbach’s alpha

11. Practicality
Economy
Convenience
Interpretability