Effect Of Structural Transition Of Urban Transit On Social Welfare

In recent years,many cities are making great efforts to build urban rail transit to meet the growing demand for rapid travel.However,in some cities,there is a continuous decline in the ridership of bus,and a large number of passengers are transferred from bus to urban rail transit.The transition of urban transit changes the choice of passengers and the environmental effect.This brings a key problem: Is the transition from bus to urban rail transit really better?In other words,how does the structural transition of urban transit affect social welfare?In the literature,as more focused on the competition between public transportation and private transportation,several studies have discussed the relationship between bus and urban rail transit.Also,environmental factors are rarely considered when discussing the effect of transportation on social welfare.In particular,the existing empirical research still have the problem of lacking micro mechanism and widely existing different results.It is necessary to answer the following two questions: What is the theoretical mechanism of the effect of the structural transition of urban transit on social welfare? Is there any difference in the effect on social welfare in different scenarios?This study mainly analyze the two core components of urban transit from the theoretical level,that is,bus and urban rail transit.Based on the literature studies,the theoretical hypothesis of "induced traffic-environmental effect-social welfare" is put forward: In the process of transition of urban transit,when there is a socio-technical transition from bus to urban rail transit,the interaction between Mohring effect and induced demand effect(induced travel)will be occurred,which may lead to energy rebound effect,increase the negative effect on environment,and eventually damage the society welfare.Based on the application framework of FSO three-dimensional comprehensive transportation theory and the duopoly competition model,this study develop a competition-cooperation model of urban transit.According to the decision-making behavior of enterprises,the endogenous model of service frequency and speed are expanded,which constitute three different scenarios.Through theoretical model derivation and numerical simulation,the findings show that:(1)The structural transition of urban transit,will lead to induced traffic,increase the total amount of urban transit,and lead to the uncertainty of effect on environment and social welfare.(2)The uncertainty is embodied the introduction of urban rail transit will sometimes improve or worsen environment,sometimes increase or damage social welfare when changeparameters in different dimensions of urban transit.This is mainly for two reasons: First,the induced demand effect by the introduction of urban rail transit may offset the positive impact of the Mohring effect.Second,the introduction of urban rail transit will affect people's consumption of other goods,making the change of social welfare related to the utility change brought by the consumption of external goods and government subsidy cost.Finally,Because the difference of urban energy in different cities,when the urban rail transit is less eco-friendly and has the higher environmental cost than bus,the introduction of urban rail transit may worsen the environment and damage social welfare.(3)The internal reason for the uncertainty that structural transition of urban transit to social welfare is that the changes of different dimensions in urban transit will actually affect the scope of uncertainty conditions.As urban transit operators can determine the increase or decrease of supply scale,the number of line structure alternatives,and how to operate.Thus,the structural transition of urban transit is a multi-dimensional change process,rather than monotonically increasing(decreasing),so that the effect of the introduction of urban rail is uncertain.Therefore,in order to improve social welfare,it is necessary to constantly improve the function dimension,structure dimension and operation dimension of urban transit.The main contribution of this study is as follows:(1)Expanding the FSO three-dimensional comprehensive transportation theory,and applying to the theoretical modeling of urban transit to social welfare.The structural transition of urban transit is attributed to the change process of function,structure and operation,which enriches the existing comprehensive transportation theory research.(2)Improving the model design that most of previous studies regard urban transit as a whole,and developing the duopoly competition model of current studies.Considering the difference of returns to scale,cooperation of urban transit and external goods consumption,the multi-scenario theoretical model is of great significance to the innovation and development of Duopoly Competition Model in the field of transportation.(3)Putting forward the theoretical hypothesis of "induced traffic-environmental effect-social welfare",which provides a micro mechanism supplement for traffic rebound effect theory and the interdisciplinary research of transportation economics and environmental science(4)Providing new methods for the urban transit enterprises to improve social welfare in multi scenario.Based on the basic conclusions of three scenarios analysis,this study summarizes the systematic and multidimensional methods to improve social welfare in the structural transition of urban transit.Combined with the theory of behavioral economics,thispaper proposes three ways to improve social welfare,which are market scale optimization based on behavioral feedback,structural alternative selection based on endowment effect and time cost difference operation based on reference dependence.It is helpful for urban transit enterprises and government departments to design,plan and nudge urban transportation development and improve social welfare according to specific scenarios.