Validity

Question 1

What are the three types of validity?

Answer 1

• Ecological Validity
• Population Validity
• Construct Validity

Question 2

What is the definition of validity?

Answer 2

How accurate a piece of research or test is at measuring what it aims to measure (is the study measuring what it is supposed to measure?)

Question 3

What is the background to validity?

Answer 3

• What we want to measure is the dependent variable (DV)
• If we are measuring anything apart from the DV by mistake, then the study is not valid

Question 4

Why could Milgram not tell his participants that the study was about obedience in the first place?

Answer 4

• If participants realised the study was about obedience, they might not act naturally
• They could either act more obedient (because they think the experimenter wants that and they want to please him)
• Or they might be less obedient because they want to ‘beat’ the experimenter
• Either way, we are not measuring their obedience anymore and therefore the study is not valid

Question 5

Independent variable (IV) meaning

Answer 5

An aspect of the experiment that is manipulated to see its effect on a particular behaviour - the behaviour that is tested

Question 6

Dependent variable (DV) meaning

Answer 6

The measure of behaviour in an experiment. Assuming the experiment is properly controlled, it can be assumed to be affected by the IV

Question 7

Extraneous variable (EV) meaning?

Answer 7

An undesirable variable that might affect the relationship between the IV and DV (EVs reduce validity)

Question 8

Demand characteristics meaning

Answer 8

When the participants realise the true purpose of a study and act differently

Question 9

What is the meaning of ecological validity?

Answer 9

Where research is true to life (does the study represent a real-life situation)

Question 10

Why is ecological validity important?

Answer 10

We want to understand how people behave in their everyday lives. However, often psychological research takes place in lab-like settings which don’t resemble anything that would happen in “real life”

Question 11

What is the meaning of population validity?

Answer 11

How accurately a sample represents its intended population (ability to generalise to other groups of people)

Question 12

Why is population validity important?

Answer 12

Researchers want to understand how as many people as possible behave. However, research just uses samples of participants who may behave completely differently from other people not included in the research

Question 13

What is the meaning of internal validity?

Answer 13

Where research does not have lots of extraneous variables and the effect of the IV on the DV is truly being measured

Question 14

What is the meaning of external validity?

Answer 14

Where research can be generalised to other setting (e.g. population validity and ecological validity)

Question 15

ECOLOGICAL VALDITY - MILGRAM
What could participants do in the study?

Answer 15

Administer electric shocks to another person every time they got an answer wrong on a memory test

Question 16

ECOLOGICAL VALDITY - MILGRAM
Explain why the study may lack ecological validity (which parts of the research seem to be unrealistic and not true-to-life?)

Answer 16

Not something most people would experience everyday

Question 17

ECOLOGICAL VALDITY - MILGRAM
Which elements of the study do seem true to life? What parts have high ecological validity?

Answer 17

People working in the Nazi death camps were also required by authority figures to inflict harm upon other people

Question 18

ECOLOGICAL VALIDTY - PILIAVIN
What could participants do in the study?

Answer 18

Decide whether to help somebody involved in a staged/fake incident on a subway train, i.e ill victim or drunk - collapsing in front of them

Question 19

ECOLOGICAL VALIDTY - PILIAVIN
Explain why the study may lack ecological validity (which parts of the research seem to be unrealistic and not true-to-life?)

Answer 19

The study took place during the daytime (weekdays 11am - 3pm), so participants may not expect to see people drunk on the train at that time

Question 20

ECOLOGICAL VALIDTY - PILIAVIN
Which elements of the study do seem true to life? What parts have high ecological validity?

Answer 20

Being on a subway train is something they would normally do and they may see drunks on the train anytime of the day

Question 21

ECOLOGICAL VALIDITY - BANDURA
What could participants do in the study?

Answer 21

Watch a role model attack a bobo-doll for 10 minutes and then be put into a room with lots of toys

Question 22

ECOLOGICAL VALIDITY - BANDURA
Which elements of the study do seem true to life? What parts have high ecological validity?

Answer 22

Children may normally see adults being aggressive in other situations

Question 23

ECOLOGICAL VALIDITY - BANDURA
Explain why the study may lack ecological validity (which parts of the research seem to be unrealistic and not true-to-life?)

Answer 23

Children would not normally see adults attacking toys

Question 24

POPULATION VALIDITY - MILGRAM
What was the sample for the study?

Answer 24

40 males from the New Haven area. Ages 20 - 50
Wide range of occupations

Question 25

POPULATION VALIDITY - MILGRAM
Why might the sample lack population validity? Why might it not be generalisable to others not in the research?

Answer 25

No females. Only collected from one area. Did not cover all occupations

Question 25

POPULATION VALIDITY - PILIAVIN
What was the sample for the study?

Answer 25

4450 New York subway train passengers. 45% were black, 55% were white

Question 26

POPULATION VALIDITY - MILGRAM
Why might the population validity to be considered high?

Answer 26

Was the same gender/age range of Nazi officers in second world war.
Study variations all over world

Question 27

POPULATION VALIDITY - PILIAVIN
Why might the sample lack population validity? Why might it not be generalisable to others not in the research?

Answer 27

Only from one city. May have had many locals people on train

Question 28

POPULATION VALIDITY - PILIAVIN
Why might the population validity to be considered high?

Answer 28

The study was carried out in New York, which is a very diverse city. The sample included people from different ethnic backgrounds

Question 29

POPULATION VALIDITY - BANDURA
What was the sample for the study?

Answer 29

72 Children from Stanford Nursery School. Aged 3-5yrs.
36 boys, 36 girls

Question 30

POPULATION VALIDITY - BANDURA
Why might the sample lack population validity? Why might it not be generalisable to others not in the research?

Answer 30

Only from one city. May have had many locals people on train

Question 31

POPULATION VALIDITY - BANDURA
Why might the population validity to be considered high?

Answer 31

The study was carried out in New York, which is a very diverse city. The sample included people from different ethnic backgrounds

Question 32

CONSTRUCT VALIDITY - MILGRAM
What was the study trying to measure?

Answer 32

How obedient participants are

Question 33

CONSTRUCT VALIDITY - MILGRAM
Are there any factors (unrelated to the aim of the study - extraneous variables) that could have influenced participants’ behaviour?

Answer 33

Milgram didn’t do much to ensure participants were all psychologically healthy. Milgram would not have been testing obedience if a person enjoyed hurting people and shocked the learner for pleasure

Question 34

CONSTRUCT VALIDITY - MILGRAM
What did the researcher do to try and ensure that they were measuring what they wanted to? (e.g. How were extraneous variables controlled for? Did participants know the aim of the study?)

Answer 34

The setting of Yale University and the use of trial shocks made it seem real. Participants stressful reactions suggested they thought it was real. Wide range of occupations controlled for possible individual differences in personality

Question 35

CONSTRUCT VALIDITY - PILIAVIN
What was the study trying to measure?

Answer 35

How helpful participants are

Question 36

CONSTRUCT VALIDITY - PILIAVIN
Are there any factors (unrelated to the aim of the study - extraneous variables) that could have influenced participants’ behaviour?

Answer 36

As the same train line/times were used it is possible some passengers on the trains saw the incidents more than once.
Cultural stereotypes or gender influences for helping behaviour were not assessed before the study (“its for men to help”)

Question 37

CONSTRUCT VALIDITY - PILIAVIN
What did the researcher do to try and ensure that they were measuring what they wanted to? (e.g. How were extraneous variables controlled for? Did participants know the aim of the study?)

Answer 37

The victims always fell in the same place, so there is less chance of he environment changing the participants helping behaviour. Passengers didn’t know thy were taking part in a psychological experiment (and that the ‘victim’ wasn’t collapsing for real)

Question 38

CONSTRUCT VALIDITY - BANDURA
What was the study trying to measure?

Answer 38

If participants imitate role models

Question 39

CONSTRUCT VALIDITY - BANDURA
Are there any factors (unrelated to the aim of the study - extraneous variables) that could have influenced participants’ behaviour?

Answer 39

The bobo-doll was not real. Children may react differently to a toy compared to a real person

Question 40

CONSTRUCT VALIDITY - BANDURA
What did the researcher do to try and ensure that they were measuring what they wanted to? (e.g. How were extraneous variables controlled for? Did participants know the aim of the study?)

Answer 40

Conditions were all controlled standardised - all children were given the same trials/conditions. Differences in aggressive behaviour showed these differences

Question 41

EXAM STYLE QUESTION
Evaluate the validity of Milgram’s study of obedience (6 marks)

Answer 41

The study by Milgram can be seen to have construct validity as the aim of the study was hidden from participants. For example, the posters that were used to recruit participants stated that the study they were volunteering for was about “memory and learning”, not obedience (the real aim of the study). This is beneficial because participants would not have acted naturally had they known their obedience was being tested. As participants were not told the true aim, we can assume the participants responses accurately reflected their true levels of obedience.

The study by Milgram can be seen to lack population validity because.. the sample was only males. For example, there were only 40 20-50 yr old males used, no females or people over 50 or under 20. This is a problem because the ability to compare or generalise results to other groups of people is important in Psychology and in this case the ability to do so is extremely limited (i.e. low population validity).