Examples of Famous Experiments
What Can WE Learn from THEM?
Where Did They Get Their Research
Question?
Zimbardo
Ash
Milgram
Examples – Famous Experiments
Where Did They Get Their Research Question?
Ash
Research on Conformity
Holocaust
Milgram
Research on Obedience To Authority
Holocaust
Zimbardo
Research on Social Roles
Holocaust
Examples of Famous Experiments

Zimbardo’s Experiment
– Quasi Field Experiment
– Examples - need for IRB

Milgram’s Experiment
– Single Shot – One Shot Design
– Intervention – Post Test
 X-----Y
– Example – need for IRB

Ash’s Experiment
– Classical Design
– Pre-test -----Intervention-----Post-test
 Y----X-----Y
Zimbardo’s Quasi Field
Experiment

Independent Variable

Dependent Variable
Zimbardo’s Quasi Field
Experiment

Independent Variable
– Social Role - Position of Power

Dependent Variable
– Behavior of Participants
How does a person’s social role influence their
behavior toward others??
Zimbardo
Prisoners Dilemma

Guards and Prisonners in Prison Setting
 Sample Technique
 Convenience Sample
 Recruited 75 volunteers
 Selected most stable 21
 Random Assignment
 Divided into Guards and Prisoners (11 and 10)
 Data Collection
 Quasi or Field Experiment
 Put respondents in simulated prison situations
 Turned Guards loose for two week
 Observed interactions
Zimbardo
Prisoners Dilemma

Guards and Prisoners in Prison Setting
 Results
 1/3 Guards demanded degrading behavior
 1/3 Guards were fair but tough
 1/3 Guards were kind – but didn’t help with other guards
 Initially Prisoner rebelled
 Prisoners became demoralized
 Experiment was ended in 6 days
Quasi Field Experiment
Milgram’s Experiment
 Independent Variable
– Concept – Authority Figure’s Power
– Indicator – Presence of Authority Figure
 Varied proximity to authority figure

Dependent Variable
– Concept – Conformity to Authority
– Indicator – Whether or not they would follow
authority figure’s directions to shock others
These Two Experiments Are Also Famous for Another
REASON
Violation of Human Subjects Rights
IRB – Institutional Review Board
Purpose
 Protect the Right of Human Subjects
When Research is Being Done
 Protect
VULNERABLE populations
 Motivation
Holocaust
IRB – Institutional Review Board
Purpose
 Protect the Right of Human Subjects
When Research is Being Done
 Protect
VULNERABLE populations
 Motivation
Holocaust
Tuskegee Experiment
IRB – Institutional Review Board

Requirements Established by Board
– Possible Benefits MUST Exceed Possible Harm
 For respondents
– Minimize Harm
IRB – Institutional Review Board

Requirements Established by Board
– Cost/Benefits Analysis
 Social Harm
 Physical Harm
 Psychological Harm
Examples of HARM

Physical Harm
– Tuskegee Experiment

Psychological Harm (Emotional Trauma)
– Milgram Experiment
– Zimbardo’s Experiment

Social Harm (Reputation/Good Name)
– Release Zimbardo’s Tape??
Asch’s Experiment

Example of Classical Design
– Most Common Type of Experiment
– Has Experimental Group
– Has Control Group
Classical Design

Pretest
– Concept – group conformity (Y)
– Indicator – whether or not subject would report right
line or go along with group

Intervention
– Concept – group pressure (X)
– Indicator – confederates stating wrong line

Post Test
– Same as Pre-test (Y again)

Used a Control Group
Classical Experimental Design

Two Stage Sample
– Convenience
– Random Assignment into Experimental/Control

Experimental Procedure
Experimental Group
Control Group
Pre-test
Intervention
Post-test
Y
Y
X
Y
Y
Classical Experimental Design

Type of Hypothesis
– Research Question should be stated as a “difference” hypothesis
 How does the experimental group differ from the control
group on second measurement of Y
Classical Experimental Design

Major Advantage
– Can Establish causal relationship
 X and Y are related
– There is a difference between the experimental and
control groups
– There is a relationship between score on second Y and
group membership
 X comes before Y in TIME
– The difference in Y came after the introduction of X
 There is no Z variable
– Random assignment – groups are alike except for
exposure to X
Classical Experimental Design
CAUTION
You have only established the impact of X on Y in
a laboratory setting. You don’t know if X will have same
impact on Y in the “real world”.
ANOTHER Modification of
Experimental Design
Solomon Four Group Design
Advantages
Does Pre-test have impact on Post-test?
IF you take the SAT a second
time, will having taken the test,
impact score the second time?
Disadvantages
Takes more Time
Takes more Money
Contact Information
Dr. Carol Albrecht
 Assessment Specialist
 Utah State Extension
 979-777-2421
 Carol.albrecht@usu.edu
