Experiments

Observational:

• Take the world as it exists - comparisons between individal or aggragate units
• Researcher has no control over independent variable

Experimental:

• Intervention by the researcher

Allows for systematic intervention upon study participants

Tests causal relationships between factors

Need:

• Appropriate RQ
• Causal hypotheses
• Carefully designed conditions/treatments

Subjects make freely cognitive decisions, independent of researcher

1) Random allocation to groups

2) Group 1 = control, Group 2 = treatment, Group 3 = treatment

3) Pre-test

4) Treatment

5) Post-test

6) Compare

• External validity 
• Artificiality 
• Reactiveness of participants
• Lasting impact?
• Self-selection

Real world environment 

Benefits:

• Natural setting
• Clarify causality 

Drawbacks:

• Validity?

Naturally occurring events treated as interventions

Benefits:

• Avoids artificiality
• Ethical responsibility

Drawbacks:

• Issue of causality?

Rules that govern the researcher's conduct

Responsibility that the research doesn't harm participants (physically or mentally)

e.g Zimbardo Stanford prison experiment, biting finger nails etc.