Causal Analysis on Travelers' Perceptions in Traffic States

摘要

Providing the traffic information of traffic states to travelers is beneficial for them to make travel choice decisions. There exist perceived differences between travelers in traffic states, but the causal factors of those perceptions sometimes lack depth of investigation. This paper utilizes a structural equation model (SEM) to analyze these causal factors. The impacts of traffic flows and travelers' personal characteristics on travelers' perceptions in traffic states can be quantified. The empirical data were collected in the city of Beijing. 120 videos, each recording a 5-second traffic condition data, were prepared representing a variety of traffic conditions on different road sections. 106 effective participants were asked to judge the traffic states of all 120 videos and to report their perceived travel speeds and traffic states from each video clip. The results indicate that the real traffic states have relatively more impacts on travelers' perceptions than do their personal characteristics. Speed is found as the most significant factor influencing travelers' perceptions, compared to other factors like the occupancy of the traffic flows. Among the personal characteristics, travelers with different ages do have significantly different perceptions on traffic states, that is to say that age plays an important role in travelers' perceptions.