“…On the other hand, it is the scheduling and sequencing of outof-home episodes that get manifested in the form of travel patterns (Doherty and Axhausen, 1999, Scott and Kanaroglou, 2002, Vovsha et al, 2003. Finally, even among those studies that consider inter-individual interactions at an episode level, almost all of them have adopted a framework that first generates activity episodes by activity purpose, and subsequently "assigns" each of these purpose-specific episodes to a certain accompaniment type (for example, alone versus joint), typically using a discrete choice model (see, for example, Wen and Koppelman, 1999, Gliebe and Koppelman, 2002, and Bradley and Vovsha, 2005. Unfortunately, such a sequential framework cannot accommodate general patterns of observed and unobserved variable effects that are specific to each activity purpose-accompaniment type combination (see also Scott and Kanaroglou, 2002).…”