Investment is one of the important strategies and financial decisions to determine the quality of enterprise development.How to improve the efficiency of enterprise investment is the main goal of enterprise management and development.in the perfect market environment assumed by the MM theorem,the investment efficiency of the enterprise should be determined entirely by the investment opportunity of the enterprise.However,the perfect market is not in line with the real economic environment,because of the problem of information asymmetry,inefficient investment behavior in enterprises is common,the main performance is excessive investment and insufficient investment.The influence factors of investment efficiency are numerous,in addition to the internal governance structure and financial characteristics,it is often affected by various market conditions and politi cal and economic factors,and many industries will also be restricted and restricted by government policies and market environment.

The government is an important stakeholder outside the company,and the government usually redistributes resources in the way of implementing government subsidies,which to some extent plays an important role in achieving market defects,promoting economic growth and promoting investment.The data show that the government's subsidies to listed companies showed a trend of rising first and then decreasing in the sample of this study.Specifi cally,the government subsidy decreased from 100.975 billion yuan in 2008 to 39.424 billion yuan in 2009,there is a drop of 60.95%，And then steadily increased to 241.942 billion yuan in 2018,there is an increase of 139.60%.As an important source of external funds for enterprises,scholars still have different voices on the economic effects（effects）of government subsidies.Because of the special transition period of our country's economic development,it needs to be coordinated and guided by government intervention to some extent,which will have an important impact on the investment behavior of enterprises.Many scholars have begun to pay attention to the problems related to government subsidies earlier,and have also actively carried out in-depth research.The existing research on government subsidies focuses on the main influencing factors of government subsidies,or on the economic benefits of enterprises and technologi cal innovation.Less research has been done on the specific effects of government subsidies,such as the impact on the efficiency of corporate investment.

Product market competition is an important external environmental factor faced by the company,whether it is excessive investment caused by agency cost or excessive investment caused by government intervention,its investment projects will eventually participate in market competition,and the company's project investment behavior may be a response to the external competitive environment.The limited characteristics of resources will inevitably aggravate the market competition,and the market competition will help to reduce the degree of information asymmetry between enterprise management and external information users to a certain extent,and make the decision-making influence of company management more transparent and easier to observe.Product market competition can increase the opportunity of comparison,the shareholders and interest-related groups of the company can evaluate the degree of due diligence of the management of the enterprise through the performance level of the enterprise within the industry,and then form the hidden supervision of the management of the enterprise.The competitive pressure can stimulate the enterprise management to seek the high quality investment project motive force,the rational person assumes in the economic sense that the external investor can judge to distinguish the different investment project quality difference,this helps to get rid of the high quality investment project under investment dilemma.However,the existing research seldom discusses the relationship between product market competition and enterprise investment efficiency in detail from the perspective of specific industry level.

In the new normal period of high quality development of economy,both government and market will play an important role in the process of resource allocation,and will also affect the decision-making behavior of enterprises at the same time,and ultimately affect the efficiency of investment.In the promotion of domestic market economy and the intensification of international competition,the degree of competition among enterprises in different industries,regions and different business sizes varies greatly.Some tend to compete freely in the market,while others tend to monopolize,due to the reasons of policy,region,supply and demand,resource channels and so on.In the face of this situation,whether the government should respect market freedom,reduce government intervention,or protect the“weak”in market competition,and increase the provision of subsidies,will be an extremely important topic of discussion.

Based on the above problems,this paper selects the listed companies in Shanghai and Shenzhen stock market from 2008 to 2018 as the main research sample.Taking government subsidy,market competition and investment behavior of listed companies into a research framework,taking stakeholder theory,principal-agent theory,information asymmetry theory,budget soft constraint theory,enterprise investment behavior theory as the cornerstone,the following questions are investigated:first,whether government subsidies affect the investment efficiency of enterprises? Second,whether the market competition will have an impact on the investment effi ciency of enterprises,and if so,what kind of impact will it have? Will the different degree of market competition affect the policy effect of government subsidy?Third,if the government subsidy,the degree of market competition will stimulate the investment efficiency of enterprises,how to deal with the relationship between the government and the market,how to effectively use the role of market competition stimulation,at the same time,the limited effectiveness of government subsidies to the extreme.

The empiri cal results of this paper show that:first,on the relationship between government subsidies and investment efficiency,in each industry,only four industries,agriculture,forestry,animal husbandry and fishery,electricity,thermal gas and water production and supply,transportation,storage and postal,information transmission software and information technology services,have an impact on investment efficiency.Among them,the estimated coefficient of government subsidy for agriculture,forestry,animal husbandry and fishery is significantly negative,which means that the stronger the government subsidy for agriculture,forestry,animal husbandry and fishery,the lower the investment efficiency of the industry.The estimated coefficient of government subsidy for electricity,thermal gas and water production and supply is significantly positive,which means that the stronger the government subsidy for electricity,thermal gas and water production and supply industry,the more efficient the investment of the industry is.The estimated coefficient of government subsidy for transport warehousing and postal services is significantly positive,which means that the stronger the government subsidy for transport warehousing and postal services,the more efficient the investment in the industry is.The estimated coefficient of government subsidy for information transmission software and information technology service industry is significantly positive,which means that the stronger the government subsidy for information transmission software and information technology service industry,the higher the investment efficiency of the in dustry.In addition,according to the results of robustness test,the estimated coefficient of government subsidy is only significant in a few regions,which has an impact on the efficiency of regional investment,but the direction of effect is not consistent.The economic development of Northeast Comprehensive Economic Zone and Great Northwest Economic Zone is relatively backward,the more government subsidy investment,the stronger the inertia of regional development; while the southeast coast is relatively developed,the more government subsidies,the higher the investment efficiency.Secondly,with regard to the relationship between product market competition and investment efficiency,among the various industries,only the mining industry,manufacturing industry,electricity,thermal gas and water production and supply industry,information transmission software and information technology services,and the change in the degree of product market competition in the five industries of the financial industry have an impact on the investment efficiency of the relevant industries.Among them,the estimated coefficient of competition in the mining product market is significantly positive,which means that the greater the competition index of the product market,the weaker the competition in the product market,the higher the investment efficiency of the mining industry,which is contrary to the original assumption that the higher the competition in the product market and the higher the investment efficiency.The estimated coefficient of competition in the manufacturing product market is negative,but not significant.This means that the increase of competitive intensity in the product market promotes the investment efficiency of listed companies in manufacturing industry.The estimation coefficient of market competition of electric thermal gas and water production and supply industry is significantly negative,which means that the increase of competitive intensity of product market can help to promote the investment efficiency of listed companies in electric thermal gas and water production and supply industry.The market competition estimation coefficient of information transmission software and information technology service industry products is significantly negative,which means that the product market competition index is reduced,the product market competition is improved,and the investment efficiency of the information transmission software and information technology service industry is higher.The estimated coefficient of competition in the product market of the financial industry is significantly negative,which means that the index of competition in the product market increases,the competition in the product market decreases,and the investment efficiency of the financial industry is higher.In addition,according to the results of robustness test,the improvement of product market competition does not necessarily lead to the improvement of investment efficiency in the region,such as the Northeast Comprehensive Economic Zone and the Northern Coastal Economic Zone.As an effective mechanism to promote efficiency improvement,the process of market competition improvement is also volatile,and the impact on investment efficiency also needs to be compared with the improvement inertia caused by government subsidies,constantly adjusted,and finally can achieve theoreti cal expectations.

Third,in view of the common influence of government subsidy and product market competition on the investment efficiency of listed companies,it is not found that the estimated coefficient of government subsidy and product market competition is significant in the same industry at the same time.In each industry,only government subsidies have a negative correlation with investment efficiency.The stronger the government subsidies to agriculture,forestry,animal husbandry and fishery,the lower the efficiency of industry investment.Mining industry only product market competition and investment efficiency negative correlation,the weaker the product market competition,mining industry investment efficiency is higher.Only the product market competition has a positive correlation with the investment efficiency,and the higher competition intensity of the product market has promoted the improvement of the investment efficiency of the manufacturing industry.Information transmission software and information technology service industry only have a positive correlation between government subsidy and investment efficiency.The financial industry only has a positive correlation between government subsidy and investment efficiency.The higher the government subsidy,the higher the investment efficiency of the financial industry.Only government subsidies have a negative correlation with investment efficiency in leasing and business services.In addition,according to the results of robustness test,the estimated coefficient of government subsidy in Northeast Comprehensive Economic Zone is significantly negative,and the competition index of product market is significantly positive.Although the degree of product market competition in Northeast Comprehensive Economic Zone is strengthening,with the continuous improvement of government subsidies in Northeast Comprehensive Economic Zone,the impact of product market competition on investment efficiency in Northeast Comprehensive Economic Zone is weakening,the effect performance is not significant,and the government subsidy may have an alternative effect on product market competition.The estimated coefficient of government subsidy in the northern coastal economic zone is significantly negative,and the estimated coefficient of product market competition is negative,but not significant.The estimated coefficient of competition in the product market of the eastern coastal economic zone is significantly negative,and the estimated coefficient of government subsidy is positive but not significant.The estimated coefficient of government subsidy is significantly negative,and the estimated coefficient of product market competition is negative,but not significant.The above analysis shows that government subsidies still play a role in different parts of China,but with the continuous strengthening of market competition,there is the possibility of market competition replacing government subsidies to pro mote investment efficiency,which to some extent confirms the estimation results based on industrial classification.

In the process of studying the relationship between government subsidy,market competition and investment behavior of listed companies,the possible innovations in this paper are as follows:First,this study systemati cally analyzes government subsidies,product market competition and enterprise investment efficiency into the same framework.As two distinct resource allocation mechanisms,government subsidy and market competition exist objectively in the present economic system of our country.The dual resource allocation mechanism is formed to act as the microeconomic main body,which is different from the single resource allocation mechanism.This paper analyzes the influence of individual government subsidy and market competition on investment efficiency,identifies the impact of single resource rationing system on investment efficiency of enterprises,and also examines whether there are complementary or alternative effects between the two resource allocation systems,that is,whether the government subsidy and market competition are complementary or alternative.Secondly,based on the two dimensions of space and industry,this paper analyzes the investment efficiency of micro enterprises at three levels.Different from the existing studies generally from the national overall level to study the impact of government subsidies or product market competition on investment efficiency,because of the differences in government subsidies and market competition between different industries,different regions,and even between different industries in the same region,covering up the differences between individual industries and individual regions,the formation of countermeasures and suggestions based on the overall estimation conclusions will inevitably lack pertinence and feasibility.This paper focuses on the influence of government subsidy on the investment efficiency of enterprises,the influence of market competition on the investment efficiency of enterprises,the influence of gov ernment subsidy and market competition on the investment efficiency of enterprises is considered at the same time,and the detailed analysis and verification are carried out from the two dimensions of spatial region and industrial industry,and the conclusion of more specific and detailed research is obtained.Third,China's regional development strategy has been hovering between regional equilibrium and non-equilibrium,and the overall country has been promoting regional balanced development from 1999 to 2019,while in 2020,it began to tend to promote regional non-equilibrium development and concentrate superior resources to develop economy.Then at the beginning of the new strategy,the existing two resource allocation mechanisms are systemati cally analyzed and summarized,on the basis of which the defects and deficiencies of the two resource allocation mechanisms are identified,and then it is particularly important to consider how to balance and focus between the two systems in the context of the implementation of the future regional unbalanced strategy.

Keywords: government subsidy,product market competition,investment efficiency,overinvestment,underinvestment