Reliability Flashcards
What is internal reliability?
Extent to which a test/measure is consistent within itself
What is external reliability?
Extent to which a test produces consistent results over several occasions
What are reliability issues?
Lack of operationalised variables - makes replication impossible and makes inter-rater reliability issues more likely
Order effect - can occur in a repeated measures design
Lack of standardised procedure - jeopardise reliability
Inconsistent measuring tools - jeopardise reliability
Uncontrolled environment - jeopardise reliability
How can reliability issues be dealt with?
Increasing levels of control - use standardised procedures, instructions and scientific measuring equipment, reducing the effect of extraneous variables
Counterbalancing - Involves splitting sample into two halves where they complete conditions in opposit order, negating impact of order/practice effects
How can reliability be assessed?
- Split-half reliability testing
- Test-retest reliability
- Inter-rater reliability
What is split-half reliability?
Test asnwers are split in half and seeing whether the same of similar scores were obtained in both halves
If so, internal reliability is high; if not, it is low and individual questions would need to be re-ordered or redesigned
What is test-retest reliability?
Testing and retesting the same participants over time, with the same test, and comparing their scores
If scores are the same, the test has external reliability
What is inter-rater reliability?
Two or more psychologists produce consistent results by using a standardised procedure, agreed coding system, or correlation of their data
