In many studies persons have been found to have biased perceptions of other persons' behaviour. In traffic strongly biased perceptions of others violations have been observed. One possible reason for this bias might be easiness of detection. If an error is very easy to observe its bias of perception should be less than for more covert errors. The items of the Swedish version of the DBQ-SWE (Aberg & Rimmo, 1998) were reformulated in order to investigate drivers' perceptions of other drivers' behaviour. The questionnaire was administered on a group of 127 persons. Perceptions of others' errors and violations were compared to self reports of DBQ-errors and violations. Also the items were characterised as more or less difficult to observe. The result reveals a strong overestimation of others behaviours. The size of bias over items will be related to easiness of detection. Any result will be related to theories about driver behaviour and consequences for measures to influence drivers' behaviour will be discussed. For the covering abstract see ITRD E137489.
Abstract