Chapter 2
Research Process
Part 2: Jan. 26, 2012
Research Process steps (cont.)
• Random sampling and random assignment
– RS:
– RA:
– Results of random sampling example:
– Results of random assignment example:
• The Correlational Method: determines if two
variables are related
– Correlation coefficient: Positive, negative, or no correlation?
• Cannot make cause-effect conclusions.
– Often a third variable can explain relations between 2
variables under study
– Example?
• Need experiments to determine cause-effect
• Experimental Methods: manipulate variables in
attempt to examine cause  effect
• About 3/4ths of Social Psych research.
• Most is done in lab settings.
• 2 distinguishing factors:
– 1.
– 2.
Advantages of Correlational vs.
Experimental Research
• Adv of Corr Research:
– 1)
– 2)
• Adv of Exp Research:
– 1)
– 2)
Step 4: Interpreting results
• Independent variables: what is manipulated
– Examples?
• Song lyrics study –
• Harassment study –
• Dependent variables: observed to determine
impact of IV
– Examples?
• Song lyrics study –
• Harassment study -
• Subject variables: cannot be manipulated
– Examples -
• Statistical significance:
– Need to determine how likely it is we’d get these
results just by chance.
• External validity – questions related to whether results will
generalize
– How can this be assessed?
• Problems with convenience samples –
• Mundane realism –
• Experimental realism -
• Internal validity – questions related to whether IV causes
effects on the DV
– How can this be assessed?
• Use of control groups –
• Experimenter expectancies -
Deception
• Use of deception in some experiments
– Types of deception:
– Confederates – how are they used?
• Benefits of deception?
• Ethical concerns?
Ethical Issues
• Should reduce stress for the participant
– Cost/Benefit analysis –
• Institutional Review Board (IRB) approves
studies
– Must obtain informed consent:
– Debriefing after the study: