Trip Chaining Behavior of Older People in the US and London: Effects of Medical Conditions and Urban Form

This paper examines the relationship between the trip complexity of older people (60 years and older) measured by the number of stops they make in a tour. The data used for this analysis is the trip-chaining dataset of the 2001 National Household Travel Survey, which is a comprehensive survey of travel behavior in the United States, and the London Area Travel Survey (LATS) which is a similar survey of travel behavior in London, England. The analysis focuses on understanding the difference in the behavior of older people compared to earlier work done on this same data for the entire NHTS sample (Noland and Thomas, in press). The focus is both on examining the effect of urban form, as proxied by population density, and the effect of medical conditions of older people on their travel. The authors break down the age cohorts into sub-groups that span the range of our population of those older than 60. This helps in understanding distinctions between the travel of the “old-old” and the “young-old”. A similar analysis is done for the LATS data, but with different definitions used for some of the disability variables and with a different context of urban form, given the population density in London. An ordered probit model is used to conduct a multivariate analysis of these effects on trip complexity. The results yield some interesting findings and both similarities and differences in the travel behavior of older people compared to the entire sample, as well as (not surprisingly) differences between behavior in London versus the United States (US) as a whole.