This study measured the effect of a roadside sign, in a 50 kilometres per hour zone, that displayed one of three messages: 1. The average speed at that site: this message was designed to induce "social comparison" whereby drivers may reduce their speed in order to comply with the behaviour of the majority. 2. "Your speed is being measured": this was intended to imply surveillance whereby drivers may reduce speed in order to avoid possible enforcement action. 3. A combination of both messages, to see if both together would have a greater effect than either alone. The percentages of high and moderate speeders reduced at the site with all three messages. On the opposite side of the road, where the messages could not be seen, such speed reductions did not occur. The findings of the current study suggest that both social comparison and implied surveillance are mechanisms by which driver speed may be reduced. Signs that encourage social comparison by highlighting behavioural norms do, however, show particular promise because of their educative component. It is suggested that more emphasis should be placed on promoting appropriate behavioural norms in future road safety campaigns. (Author/publisher) For the covering entry of this conference, please see ITRD abstract no. E214058.
Abstract