Measuring Trade-Offs Between Risk and Travel Time Based on Experimental Speed Data

Users make continuous trade-offs between risk and mobility (travel time) while driving, in order to maximize the utility of their travel, which depends on different variables and it varies according to different individuals. One of the measurable outputs of this process is the speed. An on-road experiment was carried out in order to measure the speed behavior of a sample of 19 drivers on a two-lane low-volume highway. Measurements were repeated over six days in order to test if the familiarity acquired with the road can be responsible for speed changes over time. By making some hypotheses based on previous theories, the reduction of travel times due to the acquired road familiarity can be related to a conscious/subconscious shift to a more significant risk-taking behavior. These trade-offs will be analyzed throughout the paper by considering the differences between drivers and the geometric differences between different road sections.