The Human Activity-Travel Rescheduling Decision Process

Over the past few decades the activity scheduling decision process has become an important topic for transportation researchers, including how people reschedule their daily activities and travel in reaction to change. Rescheduling decisions include modifications/updates to timing, location/route, involved persons, event/mode type, and other attributes of activities/trips, as well as addition and deletion of completely new events. Such decisions occur as part of an ongoing process over time, space and across individuals. This thesis developed and applied a new data collection methodology for exploring the rescheduling decision process. The methodology had four main stages: capturing preplanned schedules; Global Positioning System (GPS) tracking; an internetbased prompted recall diary; and a final open-ended in-depth interview to explore how and why rescheduling decisions were made. A total of 40 subjects participated in the study from the Kitchener/Waterloo area of Ontario, Canada. Results strongly suggest the development of a preplan is an on-going process, wherein tentative decisions on many attributes are often made (leaving them partially elaborated on the preplan), and that certain attributes (end times, involved persons) are more likely to evolve over a longer time period, whereas others (start time, activity/mode type, and location) are planned in advance and not likely to be elaborated upon. With regard to subsequent rescheduling decisions, the methodology was able to elicit a much greater number and variety of activity conflicts and modifications from subjects compared to previous studies. The causes of these rescheduling changes also varied substantially beyond the typical activity “p;conflicts” considered in existing models, particularly interpersonal and personal impetuses of change. Past time-geography concepts are supported by these results, although there are some aspects that are unique to these rescheduling decisions. Previous conceptualizations of the activity scheduling process can also be elaborated upon given these findings. Methodologically, the strengths of this study include the successful capturing of preplans (especially partial elaboration), utilization of GPS technologies to reduce the burden of capturing observed activity-travel patterns, and the ability to fully detail each rescheduling decisions through the open ended final interview