Empirical Analysis of Decision-Making and Tour Formation Process

The decision-making processes behind activity–travel planning and tour formation are still insufficiently understood. This lack of understanding is especially true in regard to seniors, the fastest growing age group in the United States. To understand these processes, activity–travel planning data collected in the Urban Travel Route and Activity Choice Survey for Chicago, Illinois, were analyzed. In this analysis, the activity planning behavior exhibited by respondents 65 years of age and older was compared with that of respondents younger than 65. The planning horizons and flexibilities of activity–travel attributes as well as the motivations for planning decisions were analyzed. Results revealed that elderly people tended to make fewer routine and more preplanned decisions, whereas younger people made more routine or impulsive decisions. People were highly inflexible in regard to activity location choice, but they were much more flexible when making timing decisions. An analysis of tour formation revealed that advanced age played a role in trip chaining behavior and that differences between younger and older people were observed in temporal distribution of tours, the activity planning horizon, and multistop-tour mode choice. These results re important because of the general unavailability of such decision-making process data.