The central and local governments usually pay substantial amount of subsidies to public bus companies. Hence, there is a need to implement an effective bus services policy. In this paper, the bus service demand is defined as an AI-Demand System in order to estimate various elasticities such as price, cross-price and income, of buses, trains, automobiles and taxis. This model system is applied to the bus transportation demand in Japan. From the results of this empirical study this paper demonstrates the uniqueness of bus demand in Japan, and provides several recommendations for transportation policy makers.

This paper showed the existence of economies of traffic density in Japanese domestic aviation market. In analysis, we carried out simultaneous estimation of the supply-and-demand function using the prefectures' level's OD flow data. About supply-side economies of traffic density pointed out / taken into consideration by many existing researches, the existence was statistically significant as a result of estimation. Thus, when analyzing the structure of aviation market, the importance of taking economies of traffic density into consideration is pointed out. The coefficient of airport dummy variables, such as Haneda, Itami/Kansai, Shin-chitose Airport that are taken into consideration with a marginal cost function, has many positive cases. Thus, a possibility that a large-scale airport is the result of reflecting the height of a landing fee and congestion relatively compared with a local airport is pointed out.

Many cars, buses and trucks are driven on frozen river and lake, named as “winter road”, in Sakha Republic. Sakha Republic is one of the regions where the remarkable climate change will occur by global warming, then the change of available duration of the winter road will become an important issue in the near future. This article introduces how design, management and usage of the winter road are done in Sakha Republic, based on the hearing surveys and the technical standard of the winter road issued by the Russian Federal Government. Then we analyzed the effects of global warming to available period of the winter road over the Lena River near Yakutsk.