reliability and validity

If a study is completed using a standardised procedure and obtains the same results, it can be said to be reliable. 

The lab experiment is the most reliable research used in psychological research.

a. Internal reliability is the extent to which a measure is consistent with itself. External reliability is the extent to which a measure is consistent over time.

False The test-retest method measures external reliability. The same participants are given the same test (e.g., lab procedure, questions) at separate time intervals.

The split-half method measures internal reliability. The researcher splits the test in half and analyses the responses to the first half of the questionnaire compared to the second half.

Inter-observer reliability is the level of consistency between two or more trained observers when they conduct the same observation.

b. To ensure inter-observer reliability, the observation is conducted separately by each observer to avoid conformity. One observer may be influenced by the other observers.

The reliability of observations can be improved by ensuring that the behavioural categories are operationalised.

c. The reliability of lab experiments can be improved by ensuring that all aspects of the procedure are controlled and standardised.

a. and d. The reliability of interviews can be improved by using the same interviewer for each separate interview and ensuring that leading questions are not used.

False. The reliability of questionnaires can be improved by running the test-retest method and the split-half method.

c. Validity refers to the extent to which the findings of a study are representative. E.g., do the findings reflect how people actually behave in real life?

True. Internal validity measures the extent to which the results are due to the independent variable rather than the influence of uncontrolled confounding variables.

False. Ecological validity is a type of external validity.

a. Asch's research has been criticised for its lack of temporal validity. Temporal validity measures the extent to which research findings are still relevant in the current age.

b. Assessing whether a test looks like it measures what it set out to measure is an example of face validity.

Concurrent validity assesses how closely two different tests of the same behaviour agree with each other.

b. Using a control group is one way to improve the validity of lab experiments.

If participants try to guess the aim of a study this could give rise to demand characteristics.

c. The** validity of questionnaires can be improved by using a lie scale. This helps to show up **inconsistencies in the responses.

True. The validity of observations can be improved by using covert methods. Participants' behaviour is likely to be unforced and natural in a covert observation.