Abstract:In this paper, we extend previous analyses of temporal effects by examining the factors associated with activity generation and duration over four waves of the Puget sound transportation panel survey (PSTPS). A Cox proportional hazards model was specified for each of five activities: visiting, appointment, free time, personal business, and shopping. For each activity, the duration times are modeled with an emphasis on examining important higher order interactions. The results suggest that activity durations have changed significantly over the survey period. Many of the differences in activity durations over time were significant, and often associated with increasing numbers of children in the household and higher order interactions between sex and the sequencing of activities.