Reliability across all methods of investigation. Flashcards
What is Reliability?
This is when results are consistent.
If the researchers replicate the study, they will get similar results.
It can tested by questionnaires and interviews, experimental conditions and observations.
What is External Reliability?
The extent to which a measure is consistent when repeated.
For example, the results of a study are consistent with an exact replication at a different time and/or with different participants.
What is Internal Reliability?
The extent to which different parts of a measure are consistent with itself.
For example, if a 100-question IQ test is divided into two 50-question tests, the results for each set of questions with the same participant would be similar.
How can you assess Internal Reliability?
You can use the split half -method.
Explain what the split half method is.
This is when you assess measures that test one variable with multiple questions, for example, questionnaires or tests of IQ.
1) Split the test into two parts.
2) participants complete both parts
3) Test the strength of the correlation between the two parts of the measure.
4) A strong correlation indicates internal reliability.
How can you assess External reliability?
Do a Test-retest.
What is a Test-retest?
This is when you repeat the study using the same procedures/ measuring devices at different times and test the correlation between the two versions.
What is inter-observer/ inter-rater reliability?
This is when two or more observers record behaviours during the same observation using the same behavioural categories; then, they test the correlation between each tally of behaviour to identify if the behavioural categories are appropriately operationalised.
A correlation of 0.8 or higher is usually accepted as a strong correlation.
How can you improve the reliability of observations?
You can improve the training given to observers, this can improve their accuracy in assigning a particular observed behaviour to the correct behavioural category.
Pilot studies can identify poorly defined behavioural categories -reduce errors.
How can you improve the reliability of Interviews?
You can use structured interviews rather than unstructured.
The interview will include a script the interviewer can follow, ensuring the participant has a similar experience and provides answers.
The researcher can then compare responses from each participant.
How can you improve the reliability of questionnaires?
You can used closed questions to reduce the range of possible outcomes/answers.
How can you improve the reliability of experiments?
You can use standardised procedures for each participant, so they all have the same experience.
Make sure environmental conditions are the same.
Use established tests as measures rather than creating a new test.
