Validity Flashcards
Research methods
What is validity?
- the extent to which the instruments that are used in the EXP measure exactly what you intend them to measure
What are the 2 types of validity?
- internal validity
- external validity
What is internal validity?
- The tool is measuring what it is intended to measure
- the manipulation of the IV leads to observed result
What are the factors that can affect internal validity?
- extraneous variables
-confounding variables - demand characteristics
- investigator effects
- social desirability
What is external validity?
- can the findings be generalised beyond the context of the research situation
e.g to other people and places
What is ecological validity?
- a form of external validity
- extent to which the research effect is likely to be demonstrated in other settings
What are investigator effects?
occur when the presence of the investigator affects the outcome of the research
What are demand characteristics?
- when p’s try to work out the aim of the experiment and change their behaviour
- please you effect
- screw you effect
What is social desirability bias?
p’s change their behaviour or answers to present themselves in a way they deem ‘socially acceptable’
How would issues with internal validity be dealt with?
The items on the questionnaire, interview or test need to be revised.
How would issues with external validity be dealt with?
Make the sample more representative.
What is concurrent validity?
- compares your method with an already established method.
both measures should be the same if compared - if the scores correlate as a strong positive (+0.8) the test is deemed as acceptable.
What is predictive validity?
- whether the scores on the test predict what you expect them to
What is face validity?
- whether the measuring tool appears to be doing what it should
What is content validity?
- involves looking at what extent the method of measurement does indeed measure what you are asking it to
