reliability & validity

• reliability- consistency of results
• inter observer reliability:

  1. researchers have the same training and look for the same behaviours
  2. two psychologists independently observe
  3. they check for agreement
  4. a +0.8 correlation shows reliability
• improving inter observer reliability:

  -more training

  -operationalisation (specific behaviours)

  -video the behaviour, and let them view the same video
• test-retest reliability:

  1. the same person does the same test on two different occasions
  2. if they find similar results, it is reliable
  3. this could be done by a strong positive correlation of +0.8
• improving test-retest reliability:

  -standardisation (instructions, materials, procedure)

  -identify and eliminate EV’s ( could use a lab experiment)
• internal validity- a test is measuring what it is supposed to be measuring
• internal validity- it is measuring what it is supposed to be and the findings are due to only the IV. so we can establish a cause and effect relationship.
• improving internal validity:

  -minimise EV’s

  -Lab studies
• ecological validity- generalised to the real world

  improving ecological validity:

  -more natural environment

  -use tasks/materials that represent every day life
• population validity- can be generalised to the target population

  improving population validity:

  -large sample sizes

  -random/stratified sampling

  -conduct research cross culturally across different ages and genders
• temporal validity- can be generalised to the modern day

  improving temporal validity- do the test again to see if results are still accurate
• concurrent validity- close agreement between data produced by the new test and the established test. the two tests exceeds +0.8.
• face validity- it has on face value and looks like it is measuring what it is supposed to.

  you can hand research to another psychologist to see if it has good face validity