Two hundred and twenty five drivers, who stopped at gas stations on the highway were interviewed about their perceptions of safe, enjoyable, economical, and actual driving speeds, as well as on their knowledge of the speed limit on the road they were driving. These evaluations were then compared to each other as well as to the posted speed limit. Each driver also rated himself/herself on three scales relative to being a safe, a considerate, and an aggressive driver. Regardless of the actual speed limit, drivers rated economical speed as being the lowest (92 km/hr), and enjoyable speed as being the highest (105 km/hr). The speed they drove with family in the car was similar to the perceived safe speed and economic speed. In contrast, the average reported actual speed (when driving alone) was significantly above the speed limit and close to the enjoyable speed. Thus it appears that drivers adjust their speed to be a little below the level that they desire (as being enjoyable). However, the level of adjustment is relatively small, indicating that neither safety nor savings are major determinants of speed choice. Other factors which correlated significantly with the perceptions of safe, economical, and enjoyable speeds were the posted legal speed limit (road service level), driver gender, and past record of moving traffic citations. All perceived/estimated speeds were higher on the roads with higher speed limits; men estimated higher speeds than women, and drivers with repeated citations estimated higher speeds than drivers with zero or one citation only in the past two years. This survey has implications for means of affecting speed choice by relying on factors to which drivers are already sensitive such as safety, savings, and concern for others. (A) For the covering abstract of the conference see ITRD no 207828. The reprints are also available at the web - http://www.vti.se/pdf/reports/K18APart1.pdf; http://www.vti.se/pdf/reports/K18APart2.pdf and http://www.vti.se/pdf/reports/K18APart3.pdf.
Samenvatting