University of California Transportation Center

Travel demand models focus on explaining how much individuals actually travel but offer no insight into how much individuals think they travel. The authors propose that the latter is an important determinant of traveler behavior, and that actual mobility is refracted through a variety of filters that magnify or diminish those subjective evaluations of travel amounts. Linear regression models of subjective mobility measures provided by 1,358 San Francisco Bay Area commuters were estimated earlier; the focus of this article is on identifying the potential cognitive and affective mechanisms that influence subjective mobility upward or downward, after controlling for objective mobility. The authors find three major types of mechanisms: awareness-heightening, affective, and comparison-inducing. Recurring patterns of effects in these three categories are analyzed in the light of psychological and marketing research concepts including the availability heuristic, social comparison, relative deprivation, autobiographical memory, and motivation theory.