1. CONDUCTING EXPERIMENTS
CHAPTER 9
CONDUCTING EXPERIMENTS
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2. Describe the three types of dependent variables
Distinguish between straightforward and staged manipulations of an independent variable
Describe the three types of dependent variables
Self-report
Behavioral
physiological
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3. List the reasons for conducting pilot studies
Discuss sensitivity of a dependent variable, contrasting floor effects and ceiling effects
Describe ways to control participant expectations and experimenter expectations
List the reasons for conducting pilot studies
Describe the advantages of including a manipulation check in an experiment
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4. SELECTING RESEARCH PARTICIPANTS
Samples May Be Drawn From the Population Using:
Probability sampling
Nonprobability sampling
Sampling must assure external validity to generalize to other populations
Determine the Sample Size
Larger samples provide more accurate estimates of population values
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5. MANIPULATING THE INDEPENDENT VARIABLE
Setting the Stage
Types of Manipulations
Straightforward manipulations
Staged manipulations
Use of a confederate or accomplice
Strength of Manipulation
Does the study maintain external validity?
Cost of the Manipulation
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6. MANIPULATING THE INDEPENDENT VARIABLE
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© 2012 The McGraw-Hill Companies, Inc.

7. THE DEPENDENT VARIABLE
MEASURING
THE DEPENDENT VARIABLE
Types of Measures
Self-report measures
Behavioral measures
Physiological measures
Galvanic skin response (GSR)
Electromyogram (EMG)
Electroencephalogram (EEG)
Functional MRI (fMRI)
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8. THE DEPENDENT VARIABLE
MEASURING
THE DEPENDENT VARIABLE
Sensitivity of the Dependent Variable
Ceiling effect
Floor effect
Multiple Dependent Measures
Cost Measures
Ethics
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9. ADDITIONAL CONTROLS Controlling for Participant Expectations
Demand characteristics
Using unrelated filler items on a questionnaire
Placebo groups
Can control through the use of placebo effect
Used to assure external validity is maintained
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10. ADDITIONAL CONTROLS Controlling for Experimenter Expectations
Experimenter bias or expectancy effects
Research on expectancy effects
Solutions to the expectancy problem
Single-blind experiment
Double-blind experiment
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11. ADDITIONAL CONSIDERATIONS
Research Proposals
Pilot Studies
Manipulation Checks
Debriefing
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12. ANALYZING AND INTERPRETING RESULTS
Statistical Analysis of the Data
Examine and Interpret the Pattern of Results
Decide whether there really is a relationship between the independent and dependent variables
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13. COMMUNICATING RESEARCH TO OTHERS
Journal Articles
Peer Review
As many as 90% of papers submitted to the more prestigious journals are rejected
Professional Meetings
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