4- validity

Question 1

what is internal validity

Answer 1

• concerns legitimacy and what is being measured in the study
• the extent to which a test/study investigates the true effect of the IV on the DV
• researcher must observe what they intend to

Question 2

what factors reduce internal/experimental validity

Answer 2

1. investigator effects (characteristics of researcher affect participants and results)
2. demand characteristics (participants guess aim of study and change behaviour)
3. confounding variables (external variables have not been well controlled and effect DV)
4. social desirability bias (participants try to portray themselves positively by behaving unnaturally)
5. lack of operationalisation (variables not been defined and measured properly)

Question 3

what are the 2 ways to asses internal validity

Answer 3

• concurrent validity

- face validity

Question 4

what is concurrent validity

Answer 4

• establishing internal validity of a new test by comparing scores to those from an older, established test where validity is known
• if scores are similar (correlation coefficient >0.8) then new test has high internal validity

Question 5

what is face validity

Answer 5

• way to measure if test/instrument is measuring what it should
• experts in the field examine test items/questions to see if they measure what they set out to
• done by looking at questions ‘on the face of it’ (quick look over questions)

Question 6

how to improve concurrent validity

Answer 6

• remove questions that seem irrelevant or ambiguous and then test concurrent validity again

Question 7

how to improve face validity

Answer 7

• expert in the field examines all of the questions

- might decide some aren’t a good measure and may improve them or rewrite certain questions

Question 8

what other factors help improve internal validity

Answer 8

• reduce investigator effects (standardised instructions/ remove researcher)
• reduce demand characteristics (double/single blind trials)
• confounding variables (do experiment in controlled/lab setting)

Question 9

what is external validity

Answer 9

• refers to factors outside the research setting

- how well results can be generalised to other settings, people and time eras

Question 10

what are the 2 types of external validity

Answer 10

• ecological (generalise results to other settings/contexts and if study is high in mundane realism it may increase ecological validity but setting of research must be assessed)
• temporal/times (findings are true over a period of time)

Question 11

how do you assess external validity

Answer 11

1. meta-analysis (findings from studies with the same hypothesis compared and consistent findings = high ecological validity)
2. consider environment the study was conducted in (naturalistic to have high ecological validity, lab=low ecological validity as it is artificial)
3. how dependent variable was measured (task should have high mundane realism)
4. if participants were behaving naturally (shouldn’t be aware of true aim as demand characteristics occur and this effects DV so low validity)

Question 12

how do you improve external validity

Answer 12

1. reduce demand characteristics (double blind procedure (psychologist and participant don’t know aim) or single blind (participants don’t know aim))
2. use naturalistic settings to improve ecological validity (e.g. field experiments or covert observations so participants behave more naturally)