The characteristics of trip-purpose chains are examined, and a sequential model of trip chaining, which consists of history-dependent probabilities of activity choice, is developed. Statistical analyses of the study indicate that there is a consistent hierarchical order in sequencing activities in a chain where less-flexible activities tend to be pursued in a chain tends to be homogeneous. Thus activity transitions are more organized and systematic than what a Markovian model would depict. Based on these findings, a sequential model of activity choice is formulated that, in spite of its simplified representation of the history of a chain, satisfactorily represents the observed behavior. Although the focus of the model is on direct linkages between activities, the model is capapble of representing those characteristics associated with the entire set of activities in a chain. The results of the study strongly support the sequential modeling approach and indicate its practical usefulness in the analysis of trip-chaining behavior.
Abstract