Study On The Optimal Scale Of Public Infrastructure Investment In Jiangxi Province

Since reforms and opening,Jiangxi acquires huge achievement in economic construction.Especially for nearly 20 years,Jiangxi's economic growth has achieved a big step.In 2005-2016,the average annual growth rate of GDP in Jiangxi Province reached 12.39%,and public infrastructure investment,which is one of the important ?engines? for economic growth,played an irreplaceable role in the process of economic growth,which again attracted the attention of policy makers and economists.As an important part of the government's public expenditure,public infrastructure can not only directly promote the growth of the national economy,but also has positive externalities and economies of scale,and is an indispensable material basis for the development of the national economy.With the increasing scale of investment,the rationality and structural imbalance of the scale of public infrastructure investment has gradually emerged.Excessive public infrastructure investment will have a ?crowding out effect? on private capital,so it should be coordinated with the growth of the overall economy and the supply of private goods in order to achieve Pareto optimality.In view of this,what criteria should be used to measure the optimal scale of public infrastructure investment?Are the types of demand for public infrastructure in different regions the same?How to make a scientific and reasonable investment plan based on the existing investment scale of various public infrastructures?Research on these issues,with limited investment,can provide theoretical guidance and data support for the decision-making direction and scale of public infrastructure investment by the Jiangxi provincial financial authorities,which has great theoretical significance and practical guidance for Jiangxi's economic development.The research topic of this paper is the optimal scale of public infrastructure investment.Firstly,the relevant literatures on public infrastructure and government expenditure scale at home and abroad are classified and sorted out,and the gaps and the aspects worthy of further research are sought.Secondly,it reviews the related theories of public infrastructure and expounds the status quo of public infrastructure development and investment in Jiangxi Province.Thirdly,on the basis of the "inverted U" curve hypothesis proposed by Bougheas,the theoretical model of the optimal scale of public infrastructure investment is constructed,and three indicators of traffic post facilities,electric gas facilities and water environment facilities are selected to represent the public infrastructure.The investment growth rate of the infrastructure is used as an independent variable.The actual GDP growth rate of Jiangxi Province is used as the explanatory variable.Based on the panel data of 11 prefecture-level cities in Jiangxi Province from 2005 to 2016,Jiangxi Province is established based on the Barro endogenous growth model.The measurement model of the optimal scale of public infrastructure investment analyzes the optimal size of various public infrastructures in Jiangxi Province.Finally,based on the empirical data,the total amount and sub-items of public infrastructure investment in Jiangxi Province are analyzed,and then corresponding policy recommendations are put forward.Through the above theoretical and empirical analysis,the paper draws the following conclusions: In the marginal output of the three major types of public infrastructure in Jiangxi Province,the traffic postal infrastructure ranks first,higher than the other two,which is 1.9387;In the second is the power gas infrastructure,which is 1.5842;the marginal output is the water environment infrastructure,which is 0.8127.The optimal scale of Jiangxi's electric gas infrastructure,transportation postal infrastructure,water environment infrastructure and government public expenditure were 4.23%,11.21%,5.03% and 24.77%,respectively.The average annual investment scale of Jiangxi's electric gas infrastructure,transportation postal infrastructure,water environment infrastructure and government public expenditure from 2005 to 2016 was 2.80%,5.34%,7.51% and 20.53% respectively.Compared with the optimal scale,the average annual investment in power gas infrastructure and transportation postal infrastructure investment is 1.43 percentage points lower than its corresponding optimal scale and 5.87 percentage points.The annual average size of investment in water infrastructure investment exceeds the optimal scale by 2.48 percentage points.The annual average of government public expenditure is lower than the optimal size of 4.24 percentage points.It can be seen that the three investments of electricity gas,transportation postal and government public expenditure are all under their optimal scale,and only the investment in water environment infrastructure exceeds the optimal scale of the infrastructure.From the above data,it can be seen that the overall level of public infrastructure investment in Jiangxi Province is under the optimal scale,especially the transportation postal infrastructure,which is about 6% lower than the optimal scale,indicating that Jiangxi Province still needs to increase its public goods expenditure.Investment.