CONDUCTING EXPERIMENTS
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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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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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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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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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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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MEASURING
THE DEPENDENT VARIABLE
Sensitivity of the Dependent Variable Ceiling effect Floor effect
Multiple Dependent Measures Cost Measures Ethics
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MEASURING THE DEPENDENT VARIABLE
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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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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Research Proposals Pilot Studies Manipulation Checks Debriefing
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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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Journal Articles Peer Review As many as 90% of papers submitted to the more
prestigious journals are rejected Professional Meetings
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