Reliability and Validity

• Reliability - Test-Retest

  Giving the same tests to the same participants on different occasions, then correlated to ensure similarity
• Reliability - Inter-Observer Reliability

  Having two or more observers ensures behavioural categories are applied in the same way
• Reliability - Interviews

  using the same interview with each participants
• Reliability - Experiments

  Method should be easily replicable, so results should be reproducible
• Reliability - Observations

  Ensure behavioural categories are operationalised, and should have multiple observers (Inter-observer reliability)
• What is reliability?

  How consistent findings are - producing the same results each time
• What is Validity?

  Ensure the research is measuring what it sets out to measure
• Internal Validity


  The extent to which a test measure what it claims or intended to measure
• External Validity

  The extent to which a finding genuinely applies outside of the research context
• Ecological validity

  The extent to which a finding applies to other settings or environments
• Temporal Validity

  The extent to which a finding applies to other time periods
• Population Validity

  The extent to which the research can be generalised to other cultures and countries
• Concurrent Validity

  The extend to which a psychological measure elates to an existing similar measure