`Subjective norm', which captures a person's perception of social pressure, is the sum of products of an individual's belief about the significant expectations of other people (normative belief), weighted by their motivation to conform to them (motivation to comply). This paper examines the role of subjective norm in the theory of planned behaviour. In the first experiment, 50 licensed drivers were given three imaginary driving scenarios, describing various violations including dangerous overtaking and speeding in an urban area and on a main road. They were then questioned, but found the question about subjective norm difficult to answer. In the second experiment, three different hypotheses were examined, using a postal questionnaire. As expected, normative belief was found to be significantly related to intention, past behaviour, and perceived behaviour of others. However, motivation to comply formed a negative relation with intention, indicating that intention to follow speed limits was related to an unwillingness to comply with others. These findings were interpreted according to `identity theory'. It is concluded that much of the controversy about subjective norm arises because normative belief, which is the strongest predictor of intention, does not measure perceived social pressure.
Abstract