Experimental Types

• Lab Experiment


  Conducted in a controlled environment where the researcher is able to manipulate the IV and record the DV
• Strengths of Lab experiments

  Control over extraneous variables - high internal validity

  More reproducible
• Weaknesses of Lab experiments

  Lacks generalisability - low external validity

  Increases demand characteristics as participants know they’re being studies

  May not represent real life experiences - lack mundane realism
• Field experiment


  Conducted in a natural setting where the IV is manipulated and DV is recorded
• Strength of Field experiment

  Higher mundane realism - higher external validity
• Weakness of Field Experiment

  Less control over extraneous variables - cause and effect difficult to establish

  Precise replication isnt possible

  Ethical issues - participants may not know they’re being tested (Deception)
• Natural Experiment


  The manipulation of the IV is not done by the researcher, but occurs naturally
• Strength of Natural experiments

  High external validity - real life issues and events
• Weaknesses of Natural experiment

  Rare

  Participants are not randomly allocated so unsure whether the IV affects the DV
• Quasi Experiment


  An IV that is based on an existing difference between people - not manipulated
• Strength of Quasi Experiment

  Still in controlled conditions
• Weakness of Quasi-Experiments

  Cannot randomly allocated Participants - individual differences