Effects of multi-tasking, activity envelopes and travel episode characteristics on judgements of travel experience

The rapid diffusion of mobile communication technology has facilitated individuals to conduct activities whilst travelling. The impact of such multi-tasking has typically not been incorporated into current activity-based models of travel demand. Yet, the amount and nature of multi-tasking may affect the need to conduct activities during other times of the day and, therefore, activity-travel scheduling decisions in general. To address this issue, this paper presents a new conceptualisation of the utility of travel episodes, reflecting the blurring of activities and travel. Three different mathematical specifications for the utility of travel episodes are derived. Individuals' judgements of travel episode experiences collected during three months using GPS devices and a Web-based prompted recall instrument were used to estimate and compare these models. Overall, results support the formulated theory. When incorporated into large-scale agent-based models of activity-travel decisions, the models can be applied to predict the impact of transport management schemes.