✓ Validity (AO1) Flashcards
Validity
a measure of how well a test measures what it claims to measure
2 Types of Validity
internal
external
Internal Validity
the extent to which an experiment measures what it sets out to measure
did your IV produce the change in your DV
External Validity
the extent to which the findings of an experiment can be generalised to wider settings
2 Types of External Validity
ecological
- can these findings be generalised to other settings?
temporal
- will these findings hold true over time?
2 Ways to Assess Validity
face validity
concurrent validity
Face Validity
whether a test, scale or measure appears ‘on the face of it’ to measure what it’s supposed to measure
- determined by simply ‘eyeballing’ the measure and often done by an expert in the field
Concurrent Validity
compare the new test to an existing test in the same field which is already widely recognised
- as both measures are looking to do the same thing, you would expect them to correlate highly
4 Things to Improve Validity of
questionnaires
interviews
experiments
observations
How to improve the validity of Questionnaires?
include a ‘lie-scale’ to assess social desirability bias - contradictory questions
make sure ppts know their results are anonymous
Why are they bad/How to improve the validity of Interviews?
can be subjective bc of researcher interpretation
need to include direct quotes
use triangulation - multiple different sources of evidence e.g. interview + questionnaire + observation
How to improve the validity of Experiments?
use a control group as a baseline - to see if the IV truly had an effect
standardised procedures to reduce ppt/investigator effects
single-blind/double-blind procedures
How to improve the validity of Observations?
observe ppt covertly - if the ppt doesnt know they are being observed they are more likely to behave naturally
clearly operationalised behavioural categories
