Research Methods -> Reliability

Question 1

Reliability

Answer 1

a measure of consistency.

Question 2

Test‐Retest Reliability

Answer 2

the same person or group of people are asked to undertake the research measure, on different occasions. When using the test‐retest method, it is important to remember that the same group of participants are being studies twice, so researchers need to be aware of any potential demand characteristics. It is also important to make sure that there is not too much time between each test. After the measure has been completed on two separate occasions, the two scores are then correlated. If the correlation is shown to be significant, then the measure is deemed to have good reliability. A perfect correlation is 1, and so the closer the score is to this, the stronger the reliability of the measure, but a correlation of over +0.8 is also perfectly acceptable and seen as a good indication of reliability.

Question 3

Inter‐Observer Reliability (Inter-rater reliability)

Answer 3

Inter‐observer reliability refers to the extent to which two or more observers are observing and recording behaviour in a consistent way. This is a particularly useful way of ensuring reliability in situations where there is a risk of subjectivity. In psychology studies where behavioural categories are being applied, inter‐observer reliability is also important to make sure that the categories are being used in the correct manner. Psychologists would observe the same situation or event separately, and then their observations (or scores) would be correlated to see whether they are suitably similar. If the correlation coefficient of the two observers is more than +0.8 then this means the reliability is strong.

Question 4

Improving Reliability: Questionnaires

Answer 4

For questionnaires, it will be possible to identify which questions that are having the biggest impact upon the reliability, and adjust them as necessary. If it is deemed that they are important items that must remain in the questionnaire, then rewriting them in a manner that reduces the potential for them to be incorrectly interpreted may be enough.

Question 5

Improving Reliability: Interviews

Answer 5

Firstly, ensuring that the same interviewer is conducting all interviews will help reduce researcher bias; there is the potential for variation in the way that questions are asked which can then lead to different responses. Equally, some researchers may ask questions that are leading or are open to interpretation. If the same interviewer cannot be used throughout the interviewing process, then training should be provided in order to limit the potential bias. Further to this, changing the interview from unstructured to structured will limit researcher bias.

Question 6

Improving Reliability: Experiments

Answer 6

In experiments, the level of control that the researcher has over variables is one way that reliability can be influenced. Laboratory experiments are often referred to as having high reliability due to the high level of control over the independent variable(s), which in turn makes them easier to replicate by following the standardised procedures. To improve the reliability within experiments researchers might try to take more control over extraneous variables, helping to further the potential for them to become confounding.

Question 7

Improving Reliability: Observations

Answer 7

Observations can lack objectivity, since they are relying on the researcher’s interpretations of a situation. If behavioural categories are being used, it is important that the researcher is applying them accurately and not being subjective in their interpretations. One way to improve reliability in this instance would be to operationalise the behavioural categories. This means that the categories need to be clear and specific on what constitutes the behaviour in question. There should be no overlap between categories leaving no need for personal interpretation of the meaning.