1. How do we misinterpret? Common threats to validity
Chapter 5
How do we misinterpret?
Common threats to validity

2. People are Different Individual differences and “third variables”
Selection bias and nonresponse bias

3. People Change
History and maturation
Regression toward the mean

4. The Process of Studying People Changes People
The Hawthorne Effect
Testing effects
Experimental mortality (attrition)
Participant reaction bias
Experimenter bias

5. Moving from Three Threats to Two: Confounds & Artifacts
Confounds: an additional variable varies systematically with the IV or with the DV
Artifacts: important but overlooked variables that are held constant in an experiment
Confounds threaten internal validity; artifacts threaten external validity

6. Key Terms from Chapter 5 Pseudo-experiment Control group
Selection bias
Nonresponse bias
History
Maturation
Regression toward the mean
Hawthorne effect
Testing effects
Experimental mortality
Attrition
Homogeneous attrition
Heterogeneous attrition

7. Key Terms from Chapter 4 Participant reaction bias
Participant expectancies
Demand characteristics
Participant reactance
Evaluation apprehension
Cover story
Unobtrusive observations
Experimenter bias
Double-blind procedure
Confound
Artifact

8. Key Terms from Chapter 4
Double-blind procedure
Confound