Reliability Flashcards
Define reliability.
A measure of consistency. Refers to how consistent the findings from an investigation or measuring device are.
Give two ways of assessing reliability.
Test-retest
Inter-observer reliability
Define test-retest reliability.
A method of assessing the reliability of a questionnaire of test by assessing the same person (or people) on two separate occasions. This shows to what extent the test produces the same answers as this would mean it was reliable.
What do you have to be sure of when completing a test-retest?
That there has been sufficient time between the test and retest to ensure that the participant cannot recall their answers to the questions but not too long that their attitudes, opinions or abilities may have changed.
Define inter-observer reliability.
The extent to which there is agreement between two or more observers involved in observations of a behaviour. This is measured by correlating the observations of two or more observers.
How can we improve reliability in questionaires?
The reliability of questionnaires over time should be measured using the test-retest method. If low reliability is found it may be necessary to replace some of the open questions with closed questions as there will be less room for misinterpretation.
What correlation co-efficent tells us that the two data sets are reliable?
+80 onwards
How can we improve reliability in interviews?
The best way to ensure reliability in interviews it to use the same interviewer each time. For example, one interviewer may ask leading questions or ambiguous questions. This can be easily avoided by using structured questions.
How can we improve reliability in experiments?
Make sure that the conditions in each aspect of the experiment are the same each time.
How can we improve reliability in observations?
The reliability of observations can be improved by making sure that behavioural categories have been properly operationalised and that they are measurable. Categories should not overlap.
