Validity is the extent to which a measure/test measures what is is intending to measure.
Internal Validity
Whether the results can be attributed to the independent variable
External Validity
Whether the results can be generalised to different environments.
Validity Problems
Psychologists seek to make research as valid as possible, but they face a number of validity threats:
- Whether a test really measures what it claims to measure
- Whether the participant's behaviour is coming from factors other than the independent variable. Order effects, demand characteristics or experimenter bias)
- Whether the artifical nature of the test is affecting participants behaviour. (Ecological validity)
