Related Characteristics and Mechanisms for Excess Commuting in Guangzhou
广州市过剩通勤的相关特征及其形成机制

Excess commuting which reflects the efficiency of urban commuting and the potential commuting which could be saved, means the disparity between actual commuting and minimum commuting calculated by simulating residential and workplace location choice without changing the urban structure.Linear programming optimization function is adopted to calculate excess commuting of all households and subgroups divided by household structure, housing types and job types of the head and so on.The analysis shows that about 58.41% and 44.74% of the commuting are excess in 2001 and 2005 respectively which could be saved through optimization reorganization of residential and workplace location, which means that the efficiency of commuting and spatial organization of residence and workplace in Guangzhou are very low.Excess commuting has strong relationship with socio-economic characteristics and housing types of households, especially with households' income, types of Hukou (registered residence of a household), housing tenure and types, and occupation of the head.The division of household structure and income are important factors for excess commuting.The simulation of the impacts of residential and employment suburbanization shows that both residential and employment suburbanization increases the minimum commuting.Besides the errors brought by the assumptions of minimum commuting calculation models, the socio-economic systems reform, urban planning and constructions and personal residential and employment preference have great impacts on excess commuting.The reformation of related systems including housing, state owned enterprise (SOE) and land since 1978 has led to spatial reorganization of residence and workplace location in large scale, urban planning policies pay little attention to regional job-housing balance, personal residential and employment preference has great changed, all those factors interacting mutually have major impact on the production and expansion of excess commuting.