Reliability

• What does reliability in measurement refer to?

  Consistency in measurement results
• What are the two types of reliability?

  Internal reliability and external reliability
• What does internal reliability measure?

  Consistency within a method itself
• Why is standardization important for internal reliability?

  To avoid distorted final scores
• What is an example of lacking internal reliability?

  A ruler with variable centimetres
• How can internal reliability be checked?

  Using the split half method
• What does external reliability measure?

  Consistency over time when repeated
• What is an example of lacking external reliability?

  A ruler measuring different lengths each time
• How can external reliability be checked?

  Using the test/re-test method
• What is inter-rater reliability?

  Consistency between two raters' responses
• How is inter-rater reliability assessed?

  By correlating ratings from each observer
• What are the key aspects of internal and external reliability?

  • Internal Reliability:
  • Consistency within a method
  • Checked by split half method
  • External Reliability:
  • Consistency over time
  • Checked by test/re-test method
• What are the implications of lacking reliability in measurements?

  • Distorted final scores
  • Inconsistent results over time
  • Unreliable observations