摘要：AbstractIn this work we analyze the reasons for changing pre-planned activities and travels episodes considering the type of modification observed during the scheduling process. Specifically we selected a small sample from those pre-planned episodes that are no executed at all as a pilot study. The data analyzed was collected in the first wave of a weekly activity-travel panel survey carried out in Valencia (Spain) in 2010. Each survey wave consisted on a face-to-face interview to generate a pre-planned activity agenda for the following week, an activity-travel diary implemented on mobile phones to collect activities and travels as they are executed, and in-depth telephone interviews to inquire about differences between pre-planned agenda and observed activities and travels. This methodology allowed to collect data related to how respondents pre-planned activity-travel episodes and how they re-scheduled them before execution. Observed modification types provide us with information about their spatio-temporal and social flexibility. Open-ended records collected in the in-depth telephone interviews, were coded and provided a semi-formal segmentation and categorization of the changing process as the basis of our study. Spatio-temporal and social constraints, biological needs and resource constraints are differentiated along with facets of the activity-travel episodes and socio-demographic characteristics of respondents.
