This study aims at constructing a tool to examine and provide the information of changes in car market configuration, life cycle CO₂ emission from automobile transport and tax revenues due to taxation policies. In order to quantitatively estimate the effects, a model system which chases the car cohort by engine class and age is developed. It contains models which represent economic behaviors when the tax rates are changed in the stages of purchasing, owning and using of cars. As this model system can forecast the amount of existing cars by engine class and age, it makes possible to examine the effects on reducing CO₂ emissions due to the balance of rates between each stage of taxation.

This study aims to evaluate transportation policies such as subsidy to the Public Transport and TDM based on following three steps. Firstly, this study clarifies the domains of different urban transportation modes from supply side point of view, capacity and profitability. Secondly, from trip demand side, this study clarifies the dominated territories of different urban transportation modes. The criteria for this designation are generalized cost for commuting. Thirdly, the effects of various urban transportation policies on each domains and the dominated territory are compared to find applicable and effective policy sets.

In 1990's, size and budget of travel surveys has been expanded to improve transportation plans in the US. This report introduces the current new topics of transportation surveys in the US. We summarize the topics by intra-metropolitan area survey and inter-city survey. Especially, 1) Activity-Based survey, 2) Continuous survey, 3) a large size inter-city passenger or freight survey are introduced in detail. Finally, we discuss some differences of travel survey's features between the US and Japan, and we suggest the further topics to be studied in Japan.