農山村・都市間関係におけるライフステージを考慮した居住地・従業地選択行動モデル

抄録

Rural (agricultural and mountainous) depopulation problems in Japan are caused by the over-outmigration into urban areas. The primal factors of the outmigration are not only the rural socioeconomic conditions such as labour and dwelling environments but also the commuting accessibility to urban areas. The over-outmigration does not occur when the commuting accessibility is high, even if the rural socioeconomic conditions are inferior, since they can enjoy the good socioeconomic conditions in urban areas easily. On the other hand, the urban inhabitants who had inmigrated from rural areas will return to their native rural areas, if the rural socioeconomic conditions or the commuting accessibility are improved.
The migration is derived from the choice behaviour of dwelling place. The commuting trip is derived from the choice behaviour of work place conditional on the dwelling place. Standing on these viewpoints, we simultaneously analyse the migration and commuting behaviour based on a decision making process. The factor influencing the process consists of: (1) labour; (2) dwelling; and (3) commuting conditions. The inhabitant totally evaluates those conditions, and decides on his dwelling and work places. The evaluation of inhabitants differ from each other according to their life cycles if the choice conditions are identical. The choice behaviour of dwelling and work places are not independent from each other. The life cycles and this choice dependence are key points of our approach. A model for the life cycle and its changing process is incorporated with a simultaneous choice behaviour model. By this model, we can analyse the followings, simultaniously: (1) the rural population; (2) outmigration into urban areas; (3) inmigration from urban areas; and (4) commuting trips from rural to urban areas.