Household Stratification Models for Travel Estimation

Household stratification models are needed to meet the data requirements of the increasingly popular disaggregate approach for travel simulation in transportation studies. The results of various tests related to the dependence of auto-ownership on household size indicated that, for the sake of simplifying the application models, auto-ownership can be assumed to be independent of household size. However, the areawide relationship of auto-ownership with household size can be incorporated in the model by appropriate weighting. The urgent need and scope for developing synthetic or theoretical models for household stratification because of the increasing trend of using small sample origin-destination surveys are discussed. The data requirements and factors related to the forecasts of household characteristics also are analyzed and it is pointed out that the curves of a model may be adjusted based on judgment if the distribution of a household characteristic, with respect to the zonal average values of the same characteristic, is expected to change in the future.