Sherif (1935) Conformity and the autokinetic effect

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.

Strengths

• 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.

Weaknesses

• 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.