types of experiment

• what is a laboratory experiment?

  • an experiment conducted in a highly controlled environment
  • eg: a lab, classroom
• what are the advantages of a lab experiment?

  • high degree of control - greater accuracy
  • easily replicated
  • high control of confounding and extraneous variables
  • high internal validity
• what are the disadvantages of a lab experiment?

  • lack generalisability, mundane realism
  • lack ecological validity - lab setting unlike everyday life
  • participants are usually aware they are being tested - increased risk of demand characteristics
• what is a field experiment?

  • takes place in a real world setting
  • IV still being highly controlled by researcher
• what are the advantages of a field experiment?

  • higher mundane realism
  • higher ecological validity - participants less likely to be aware they are being studied
• what are the disadvantages of a field experiment?

  • loss of control of extraneous variables - precise replication not possible
  • ethical considerations - invasion of privacy, likely to have been no informed consent
• what is a natural experiment?

  • researcher has no control/ manipulation over IV
  • changes happen naturally
• what are the advantages of a natural experiment?

  • high external validity - real life situation
  • provides opportunities for research otherwise impossible for practical and ethical reasons
• what are the disadvantages of a natural experiment?

  • natural occurring events may happen rarely, hard to replicate - difficult to generalise findings
  • very difficult to randomise
  • may be conducted in a lab - may lack mundane realism, demand characteristics may be an issue
• what is a quasi experiment?

  • IV is based on existing difference between people eg: age, gender - no manipulation by researcher, exists naturally
  • DV may be naturally occurring or may be devised by experimenter
• what are the advantages of a quasi experiment?

  • carried out in controlled conditions - easier to replicate
  • likely to have high internal validity
• what are the disadvantages of a quasi experiment?

  • cannot randomly allocate participants to conditions, therefore there may be confounding variables
  • IV not deliberately changed by researcher - cannot claim IV has caused any observed change