Sherif researched whether people are influenced by others when they're doing an ambiguous task (one where the answer isn't clear).
- Labratory experiment.
- Repeated measures design.
- Used visual illusion called the autokinetic effect, where a stationary spot of light, viewed in a dark room, appears to move.
- They had to estimate how far it had moved.
- In first phase, individual participants made repeated estimates.
- Put into groups of 3 and made estimates with others present.
- Then tested individually.
- When alone participants had their own stable estimates (personal norms).
- When in groups estimates tended to converge and became more alike.
- Tested on their own again and their estimates were more like the group estimates than their personal norms.
Participants were influenced by estimates of other people, and a group norm developed.
Estimates converged because participants used info from others to help - affected by informational social influence.
- Labratory experiment - good because variables strictly controlled, meaning that a cause and effect can be identified as there's little chances of extranous variables messing with the results.
- Method can be easily replicated.
- Repeated measures design may mean that participant variables could affect the results.
- Artificial situation - lacks ecological validity.
- Sample limited so can't be generalised to everyone.
- Ethics - deception as the light wasn't moving but was told that it was.