Comparative Analysis of Household Activity Matching Approaches in Transportation Analysis and Simulation System

Transportation Analysis and Simulation System (TRANSIMS) is a microsimulation model, which uses census data to generate a synthetic population and assigns activities using activity survey data to each person of every household of the synthetic population. The synthetic households generated from the census data are matched with the survey households based on their demographic characteristics. The activities of the survey household individuals are then assigned to the individuals of the matched synthetic households. A classification and regression tree algorithm program is used to build the matching tree for the activity survey households based on some demographic independent variables. The current TRANSIMS model utilizes times spent at activities as dependent variables for building the classification tree. This research instead uses the travel times for travel between activities as dependent variables, i.e., using the travel time pattern instead of activity time pattern to match the persons in the survey households with the synthetic households. This approach assumes that if the travel time patterns are the same then we can match the survey households to the synthetic population, i.e., people with similar demographic characteristics tend to have similar travel time patterns. The algorithm of the activity generator module along with the original set of dependent variables were first used to generate a base case scenario. Further tests were carried out using an alternative set of dependent variables in the algorithm. A sensitivity analysis was also carried out to test the affect of different sets of dependent and independent variables in generating activities using the algorithm of the activity generator. The paper documents the results from all these tests and provides conclusions and recommendations.