Difference between compliance & internalisation
The relation between compliance and internalisation is complicated by how we define and measure private and public views. For example, a person who agrees with a group publicly, but disagrees privately demonstrates compliance. However, it is possible that a person who previously agreed both publicly and privately changes their views, because they forgot information given by the group or are under the influence of someone else (replacing information). Some people may also misperceive their own views (e.g. 'I agreed with the group, so I have to believe in it').
Research support for normative influence
Likenbach and Perkins (2003) found that adolencents of smoking exposed to the simple message that the majority of their age peers did not smoke were subsequently less likely to take up smoking.
Schultz et al. (2008) found that the hotel guests exposed to the normative message that 75% of guests reused their towels each day (rather than requiring fresh ones) reduced their own towel use by 25%.
These studies support the claim that people shape their behaviour out of the desire to fit in with their reference group.
Research support for informational influnce
Wittenbrink & Henley (1996) found that participants exposed to negative information aobut African Americans (which they were led to believe was the view of majority) later reported more negative beliefs about a black individual.
Fein et al. (2007) demonstrated how judgements of candidate performance in US presidential debates could be influenced by knowledge of others' reactions. Ps. saw what was suppostedly the reaction of their fellow participants on screen during the dabate. This produced large shifts in participants' judgements of the candidates' performance.