Abstract
The purpose of this study is to clarify the relationship of changing commuting distance and urban structure whether centralized or decentralized based on the optimal commuting assignment problem as defined by the classical transportation problem. The theoretical minimum and maximum commuting distance in the optimal solution leads to the calculation of three indices as named "Excess", "UCI" and "TFR". This is formulated and applied to the Census data from Korean and Japanese Metropolitan Areas from 1980 to 2000. The main results of this study show that 1) only Seoul and Busan MA indicated increasing commuting distance and high value of indices in Korea. Moreover, Busan MA showed inefficient commuting compared to Seoul MA. 2) Tokyo, Osaka, Nagoya and Fukuoka MA have more decentralized spatial structure and high Excess and TFR compared to other metropolitan areas in Japan. 3) However, Tokyo and Osaka MA could have much high cross commuting compared to Seoul MA even though those metropolitan areas have the same decentralized structure is found out