To decrease the negative consequences of a road crash, even a small reduction in driving speeds can make a significant difference. We examined the possible application of the left-digit effect as a nudge to reduce road speed. In the marketing field, this effect is based on reporting price tags that are characterized by a low leftmost number and a high rightmost number (e.g., a price tag of €14.99 rather than €15.00). We applied the same strategy to improve road safety. Participants were college students (43.75% female, mean age = 24.06 years in Study 1; 50% female, mean age = 23.53 years in Study 2) who were asked to drive in a simulator on a route that had both usual unmodified road signs (e.g., 50 km/h) and the same road signs increased or decreased by one unit (e.g., 49, 51 km/h). We compared the average median speeds in road segments with unmodified road signs with those in road segments with the corresponding modified signs. The average median speeds in the presence of a sign modified by the reduction of 1 km/h were significantly lower compared with the median average speeds recorded with unmodified signs. We showed that the application of psychological insights can reduce driving speeds and therefore increase road safety.

为了减少道路交通事故的负面影响，即使行驶速度稍有降低也可以产生重大影响。我们研究了左数字效应可能作为降低道路速度的微调的可能方法。在营销领域，此效果基于报告的价格标签，该价格标签的特征是最低的最低数字和最高的最高数字（例如，价格标签为14.99欧元而不是15.00欧元）。我们采用了相同的策略来改善道路安全。参加者是大学生（在研究1中，女性为43.75％，平均年龄= 24.06岁；在研究2中为50％，女性，平均年龄= 23.53岁），他们被要求在既有通常未修改的路标的路线上驾驶模拟器（例如50 km / h）和相同的路标增加或减少一个单位（例如49、51 km / h）。我们将未经修改的路标的路段平均速度与经过修改的路标的路段平均速度进行了比较。与未经修改的标志记录的中位数平均速度相比，在存在通过降低1 km / h进行修改的标志的情况下，平均中速显着降低。我们证明了运用心理洞察力可以降低行驶速度，从而提高道路安全性。