Simulating emergent behavior and evolution of activity-travel patterns: data collection challenges

Abstract

The aim of this paper is to focus on different aspects in regard to the collection of data about emergent activity-travel behavior and dynamically evolving activity-travel patterns. Within Flanders, no activity-travel nor panel surveys exist concerning travel behaviour, only a household travel survey is carried out every five years. Therefore, several data collection solutions are proposed and combined into an extensive hybrid, multi-method approach where every component was actually applied and implemented in practice. This paper does not provide detailed results, but rather a brief overview of the different data solutions needed, facing the problem of collecting dynamic activity and (re)scheduling information. The different decisions concerning the survey design are discussed and the major data collection is described. Detailed data on activity-travel patterns are collected using a combination of paper-and-pencil and GPS/PDA devices. In comparison with other activity-based studies, the survey period is particularly long, i.e. 7 days which is required to obtain information about the regular behaviour and two members of the household are questioned as opposed to a single household representative. The survey also includes questions about activity plans and execution and reasons for change/adjustment. Second, a data fusion exercise is undertaken, combining the Flemish travel survey data with the Flemish time use survey data. This results in a larger sample of the population and in more detailed information. Third, data are collected on traveler strategies to cope with unexpected events during execution of an activity agenda by means of stated adaptation experiments. Fourth, data on lifecycle events are collected using an internetbased retrospective survey, asking respondents which lifecycle events they experienced and when they did so. Finally, additional data on regular events are captured using a vehicle embedded data acquisition device, allowing for long-term data collection.