Research methods - validity

Question 1

define internal validity

Answer 1

questions the cause & effect relationship between the change the researcher made to the IV and the observed change in the DV. If the change in the DV was influenced by any other factor that the IV (due to a lack of control), findings lack internal validity.

Question 2

define external validity

Answer 2

questions if a study’s findings can be generalised beyond the study. So from the sample used to the target population and from the experimental set-up to other ‘real world’ settings and activities

Question 3

define ecological validity

Answer 3

the extent to which the findings of any particular study can be generalised to alternative environments, e.g. if moving a test of obedience from a lab setting to a busy city street, would obedient behaviour be replicated

Question 4

how is internal validity improved
5 points

Answer 4

1. random allocation - controls ppt variables
2. standard procedures - controls extraneous variables
3. counterbalancing - controls order effects
4. single & double-blind trials - controls researcher bias and demand characteristics
5. peer review - controls researcher bias

Question 5

define mundane realism and population validity

Answer 5

mundane realism - the extent to which the task/materials/activities used in an experimental set-up are similar to the stimuli experienced in the real world.

population validity - the extent to which the sample used in the study is representative of the target population. (e.g. gender, age, ethnicity, education level)

Question 6

define concurrent validity

Answer 6

the extent to which data from the newly created test is similar to an established test of the same variable conducted at the same time. A test of correlation assesses this; there is high concurrent validity if the strength of the correlation is +0.8 or higher

Question 7

how is external validity improved
4 points

Answer 7

• replicating findings in multiple settings improves ecological validity
• replicating findings with diverse groups of people improves population validity
• replicating historical studies improves temporal validity
• replicating findings using real-world/realistic tasks improves mundane realism