Application of Activity Chaining Model Incorporating a Time Use Problem to Network Demand Analysis

An activity chaining model described as a time use problem is presented. Unlike existing activity chaining models, the time use problem includes all choice attributes related to time, not only when and where the activity is performed but also the duration of the activity. To apply the time use problem to transportation network demand analysis, the opportunity cost of travel time is modeled through a constraint approach, and the value of activity is represented by time-dependent utility profiles. In the model, among activity alternatives, the activity with the biggest utility is sequentially included within an individual's daily disposable income. Through the sequential selection process, not only the activity type but also its start time and duration are simultaneously determined on the basis of an individual's perceived time-dependent travel time for the activity. Since the activity chaining is performed on the basis of the dynamic travel times calculated via traffic network simulation, the activity chaining is iteratively updated through a day-to-day dynamic process. The model is applied to a medium-size network to show its applicability. The example sheds light on the practicality of activity-based models and extends applications of the travel demand model to market analysis by illustrating how the model can analyze impact of transportation network improvement on the activity pattern and zonal socioeconomic conditions particularly associated with shopping and leisure activities.