validity

• what is concurrent validity

  • A means of establishing validity by Comparing current method with a validated existing test 
  • Participants given both at same time and scores compared (should be similiar)
• what is face validity

  • Face validity is the extent to which test items looks like what the test claims to measure
  • only requiring intuitive measurement
  • eg.are the questions on a stress questionnare related to stress
• validity definition

  refers to whether an observed effect is a genuine one and whether a test actually measure what it claims to measure
• internal validity problems

  1. investigator effects
  2. demand characteristics
  3. confounding variables
  4. social desirability bias
  5. poorly operationalised behavioural categories
• improvements for face and concurrent

  bad face= questions should be revised so they relate more obviously to the topic

  bad concurrent= researcher should remove questions which seem irrelevant and check again
• how to improve internal external validity

  improve research design eg. using double blind experiments
• reasons for bad external validity

  • sample bias- some population have more chance being selected
  • not a representative sample
  • artificial or contrived environment