Validity is how far the research measures what we intend it to measure
External validity is whether the findings of a study can be generalised to situations and people other than those in the study, eg locations and populations.
Milgrams experiment was based on American males between 20-50 from New Haven and Asch's students were all his own and all American males. Findings from such studies can't be generalised to other populations.It has also been suggested that women are more likely to conform than males - this has been disputed and explained by a type of conformity task (sistrunk and mcdavid 1971.) However, milgram later replicated his experiment with women and found similar obedience. also, would it be applicable to other periods of time? In Asch's study, people were from individualist cultures and further studies showed a higher error rate in collectivist cultures.
Studies in other cultures have produced various rates of obedience but comparisons are hard to make because their methology differs
Asch's experiment was carried out during the cold war when there were witch hunts chasing people who acted in a non-American way. Larsen replicated Asch's study on American males and did find lower conformity rates.
Research has also found conformity to be lower in student than non student populations
Asch's line judging and sherif's light judging bear little resemblance to everyday life, but Asch deliberately chose an unambiguous task as he wanted to measure pure conformity.
Critics say Milgrams doesn't reflect real life and any obedience could be due to demand characteristics. Bickman's field study, however, produced similar findings to Milgrams study in a realistic setting.
Milgram stated that psychological processes in obedience are essentially the same regardless of whether the setting is artificial or natural
A 'real life' study high in ecological validity was Hofflings nurse study
Hofflings study 1966
It was very high in ecological validity and the nurses were unaware they were taking part
AIM- investigate obedience
METHOD- involved a naturalistic field setting involving 22 (real) night nurses. Dr Smith (a stooge) phones the nurses at the hospital (on 22 occasions) and asks them to see if they have the drug astrotin. When the nurse checks she sees the max dose is 10mg. The doctor tells to give 20mg to the patient. Smith was in a hurry and stated he would sign the authorisation form later. The medicine wasn't real but the nurses thought it was. If the nurse administers the drug she would have broken three hospital rules- accepting instructions over the phone, double dosing and using medicine that was unauthorised (not on the stock list.) The drug was a sugar placebo.
RESULTS- 21 of 22 nurses were easily influenced into carrying out the orders. Other nurses discusses what they'd do in the situation, and 21 of 22 said they wouldn't comply
CONC- Hoffling demonstrated people are very unwilling to question authority, even if they have good reason to
Internal validity is whether it is only the IV that manipulates the DV
Critics claim in a number of experiments there were demand characteristics. Some of Asch's participants did say they gave the wrong answer and conformed because they didn't want to spoil the experiment or upset the experimenter. In sherifs experiment, where the task is ambiguous, participants may appear to be conforming but were, in fact, respondingnto demand characteristics. It has also been argued that Milgrams participants obeyed due to demand characteristics, but this is unlikely as they were all given sample shocks and suffered various degrees of stress.
Bickman's and Hofflings participants weren't even aware a experiment was taking place.
As researchers, psychologists confront important ethical issues:
o how will the participant be used in the research and can this be justified?
o Is the research important and of value, outweighing any harm done?
In the UK the BPS (British psychological society) have specific ethical gudelines bad on these principles
Use of deception
The principle states deception should be avoided, wherever possible. Asch and Milgram deceived their participants of the study purpose and the role of other participants. Sherif and Gamson also deceived their participants of the study purpose. However, without this deception these studies would lack internal validity.
Some psychologists suggested role playing but the potential costs needs to be weighed against the potential benefits of experiments using deception.
According to Hogg and Vaughn some deception is 'essential to preserve the scientific rigour of much experimental and social psychology.'
Respect for privacy
It's sometimes to decide whether the research topic justifies invasion of privacy. Hofflings and Bickman's participants didnt know they were part of a study - but both internal and ecological validity was strengthened.
Unless participants know the aim and procedure and are fully informed of the study, they can't give informed consent. The deception in the studies ruled out informed consent and Milgrams participants didn't excersize their right to withdraw - they were ordered to keep giving shocks.
A way around this is to obtain presumptive consent (obtaining the views of other people of the acceptability of the procedures. It is assumed participants would feel the same way.) Milgram obtained this consent from his students and psychiatrists.
Debriefing allows the researcher to obtain informed consent retrospectively and put right any deception. The deception and aims are explained to the participant and they also have the right to withdraw their results. Milgram fully debriefed his participants but it's questionable whether a debrief puts right the knowledge of knowing one was strong enough to give shocks enough to kill someone, and give pills to kill someone (Hoffling)
Protection from harm
Participants should be fully debriefed so they feel no worse after the experiment than they did before. Any possible harm should be no greater than real life.
Asch's participatns suffered from stress. This was confirmed by psychological measures of arousal - but we frequently find ourselves in disagreement of others so any discomfort was not out of the ordinary. Milgrams participants suffered from stress, one even from convulsions. But all were debriefed and 84% said they were glad to have taken place and none suffered long term disturbances.
No ethical concerns were raised when Milgram got presumptive consent, so maybe the study wouldn't have attracted so much criticism had the results been different.
Is the research important and of value?
Sherif and Asch's studies showed that people will conform to implicit group pressure. Findings from obedience studies highlight the power of authority and the capacity for ordinary people to carry out terrible deeds.
However, some don't believe they constitute real life and some argue it is creating an alibi for situations like the holocaust which are crimes against humanity (Mandel 1998)