The current portfolio model for property-liability insurance company is only single period that can not meet the practical demands of portfolio management, and the purpose of this paper is to develop a multiperiod mod...The current portfolio model for property-liability insurance company is only single period that can not meet the practical demands of portfolio management, and the purpose of this paper is to develop a multiperiod model for its portfolio problem. The model is a multistage stochastic programming which considers transaction costs, cash flow between time periods, and the matching of asset and liability; it does not depend on the assumption for normality of return distribution. Additionally, an investment constraint is added. The numerical example manifests that the multiperiod model can more effectively assist the property-liability insurer to determine the optimal composition of insurance and investment portfolio and outperforms the single period one.展开更多
Coal dependence and inefficient decentralized heating have significantly increased China’s energy consumption for winter heating,increasing air pollution and exacerbating the greenhouse effect.In 2017,China implement...Coal dependence and inefficient decentralized heating have significantly increased China’s energy consumption for winter heating,increasing air pollution and exacerbating the greenhouse effect.In 2017,China implemented the Pilot Policy on Clean Winter Heating in Northern China,aiming to achieve high central heating coverage and cleaner energy consumption.Studying the effects of this policy can help promote its implementation and serve as a reference for effective adjustment of the contents in the future.However,few studies have investigated this policy and its carbon reduction effects,and most focus on the provincial or city levels.Therefore,this paper considers the policy’s influence on air pollution and carbon emissions at the county level to provide a precise and comprehensive assessment of the policy effects.We use panel data from 1290 counties in 15 provinces in Northern China from 2014 to 2021,applying a multiperiod difference-in-differences model to quantify the impact of the policy on carbon emissions and air quality in the pilot area.We then conduct a series of tests to demonstrate the robustness of the results and analyze the mechanisms of the policy effects from two perspectives,namely,central heating and natural gas use,through a mediating effect model.Finally,we examine the heterogeneity of policy effects between counties based on geographic location and per capita income levels of rural residents through a moderating effect model.The results reveal that the policy significantly reduces air pollution and carbon emissions in the pilot area by increasing the central heating area and natural gas use.Compared with the central and western regions in the north and areas with low-income rural residents,the policy effects in the eastern regions in the north and areas with high-income rural residents are more pronounced.展开更多
As urbanization accelerates globally,air pollution-particularly PM_(2.5)-is becoming an increasingly significant threat,not only to public health but also the environment.In-depth research on the impact of China’s Ze...As urbanization accelerates globally,air pollution-particularly PM_(2.5)-is becoming an increasingly significant threat,not only to public health but also the environment.In-depth research on the impact of China’s Zero Waste City pilot policy on PM_(2.5)concentration offers valuable insights into the policy’s effectiveness and provides a potential model for environmental governance worldwide.This study employs panel data from 293 Chinese cities from 2014 to 2022 to systematically analyze the impact of the Zero-Waste City policy on PM_(2.5)concentration using a difference-in-differences model.The findings indicate that the policy not only directly reduces PM_(2.5)concentration but also indirectly curbs PM_(2.5)emissions by enhancing green innovation and green economic efficiency.Moreover,the policy’s effects are found to be positively moderated by urban energy dependence and digital financial inclusion,while they are negatively moderated by the government debt ratio.Based on these findings,this study suggests that cities should actively develop their digital economy,reduce government debt,promote green innovation,and improve green economic efficiency,as doing so will enhance their implementation of environmental policies and promote sustainable urban development.展开更多
To effectively solve the problem of environmental pollution,the Chinese government has implemented an environmental supervision system since 2002.The environmental supervision system mainly uses the four functions of ...To effectively solve the problem of environmental pollution,the Chinese government has implemented an environmental supervision system since 2002.The environmental supervision system mainly uses the four functions of supervision,investigation,coordination,and emergency response to strengthen environmental protection supervision and law enforcement,respond to environmental emergencies,and coordinate cross-regional pollution disputes.As an important system design for China to control environmental pollution and promote the ecological transformation of economic development,the policy effect of the environmental supervision system deserves attention.This paper uses the difference-in-differences method to investigate the impact of the top-down environmental supervision system on air quality based on the 2000-2016 data for 285 prefecture-level cities in China.The results indicate that the annual average concentration of PM_(2.5)decreased significantly after the implementation of the environmental supervision system.The dynamic analysis shows that PM_(2.5)decreased most markedly in the first year after the implementation of the policy,and then the effect gradually weakened.Mechanism analysis suggests that the environmental supervision system can break the collusion between government and enterprise,encourage enterprises to carry out technological innovation,change pollutant discharge behavior and push local governments to adjust the industrial structure,enhance environmental protection awareness to reduce the PM_(2.5)concentration,and improve air quality.Comparing different regions,the PM_(2.5)in East China,North China and Northeast China are relatively high,and the pressure for air pollution control is great.Meanwhile,we find that the environmental supervision system has a significant station effect.Compared with other cities,the cities where the environmental supervision centers are located are more deterred by the environmental supervision,and their air quality has improved to a significantly greater degree.In the future,we should further strengthen the environmental supervision of high-pollution areas and non-station cities,and pay more attention to improving the long-term effect of the environmental supervision system.展开更多
The green credit policy(GCP)is an essential financial policy tool for solving the problem of environmental pollution,and urban energy conservation is an effective way to achieve the goal of carbon neutrality.However,e...The green credit policy(GCP)is an essential financial policy tool for solving the problem of environmental pollution,and urban energy conservation is an effective way to achieve the goal of carbon neutrality.However,existing research has not verified the energy-saving effects of green credit(GC)at the city level.Based on panel data from 283 cities in China,this study aims to investigate whether GC can effectively reduce urban energy intensity(EI),which is an important complement to existing research.In terms of research methods,to better evaluate the effect of the policy and exclude the influence of other relevant factors,this study considers the promulgation of the Green Credit Guideline(GCG)in 2012 as the basic event,uses the difference-in-differences(DID)model to investigate the impact of GC on EI,and discusses the main impact mechanism.The key results are follows.(1)GC can effectively reduce urban EI.(2)Public environmental demand positively regulates the negative correlation between GC and EI.(3)GC reduces EI through three main channels:government support,capital investment,and technological innovation;however,the mechanism of industrial structure has no significant effect.(4)The effect of GC is more significant in areas with large urban scales,low environmental regulation intensity,and high industrial agglomeration.Based on the above results,this study presents puts forward targeted policy recommendations to strengthen the role of GC in urban sustainable development.展开更多
Long-term exposure to fine particulate matters(PM_(2.5))has been associated with respiratory and cardiovascular diseases and the burden are potentially higher in China experiencing heavy air pollution.In this study,we...Long-term exposure to fine particulate matters(PM_(2.5))has been associated with respiratory and cardiovascular diseases and the burden are potentially higher in China experiencing heavy air pollution.In this study,we established the exposure-response association between long-term exposures to PM_(2.5)and lung function and blood pressure in Chinesemiddle-aged and older adults using linearmixed-effects and generalized additive mixedmodels based on 3 waves longitudinal health outcomes data by enrolling 19,988 participants from 121 cities across themainland of China.We also assessed the effect of Clean Air Policy(CAP)based on a quasi-experimental difference-in-differences(DID)design.A 10μg/m^(3)increase in PM_(2.5)concentration was associated with a 7.18(95%confidence interval[CI]:-8.35,-6.02)L/min decrease in PEF(peak expiratory flow)and a 0.72(95%[CI]:0.53,0.90)and a 0.30(95%[CI]:0.18,0.42)mmHg increase in systolic and diastolic blood pressure,respectively.The associations were more pronounced in males and rural areas for PEF,but similar across subgroups for blood pressure.DID results suggested that the effect of CAP on health outcomes were sensitive tomagnitudes of reduction in PM_(2.5).A 5μg/m^(3)reduction in PM_(2.5)or more generally led to 18.70(95%[CI]:0.79,36.61)higher PEF and-2.05(95%[CI]:-3.87,-0.23)lower diastolic blood pressure,respectively,compared to no reduction or increase in exposure.However,the effects were significant only in rural areas.Our analysis support CAP aiming to benefit public health and provides insights to inform future control policy for efficiently decreasing air pollution exposure burden.展开更多
As a unique environmental regulation in China,the official accountability audit was piloted in 2014.With a focus on prioritizing the ecological environment,officials in pilot districts have implemented economic constr...As a unique environmental regulation in China,the official accountability audit was piloted in 2014.With a focus on prioritizing the ecological environment,officials in pilot districts have implemented economic construction,adjusted industrial structures,and promoted coordinated development between the economy and environment.The effects of implementation have garnered widespread attention from society.However,there is limited research on the impact of an accountability audit on industrial structure adjustments.Using the“Accountability Audit of Officials for Natural Resource Assets(Trial)”released in 2015 as a quasi-natural experiment,this study collected panel data from 279 cities between 2013 and 2017.It then empirically analyzed the impact mechanism and effects of the accountability audit on industrial structure adjustment using the Propensity Score Matching and Difference-in-Differences model.The research findings indicate that the accountability audit directly impacted industrial structure adjustment,promoting the upgrading of the primary industry to the secondary industry and restricting the development of the tertiary industry.In addition,the audit is beneficial for enterprise entry,but not conducive to technological innovation,and has no significant impact on foreign direct investment.This conclusion fills a gap in the existing research and provides valuable insights for policymakers.展开更多
There is a worldwide consensus that excessive anthropogenic carbon dioxide emissions will lead to global warming and other environmental problems.Supports from regulations and policies have gradually implemented in th...There is a worldwide consensus that excessive anthropogenic carbon dioxide emissions will lead to global warming and other environmental problems.Supports from regulations and policies have gradually implemented in this area.As one of the most discussed policies,the carbon emissions trading schemes(CETS)has an advantage in its price-oriented and cost-saving characteristics.In this paper,we analyze and assess the CETS effect from static and dynamic perspectives by applying provincial panel data covering a period ranging from 2004 to 2017.The CETS policy has a significant constraining effect on both carbon emissions and primary energy consumption.Compared to the other two uncertainties,namely the energy price uncertainty and the technology uncertainty,the carbon permit price uncertainty has a relatively smooth impact on the economy,which is being pursued consistently by the policymakers.展开更多
The innovative city pilot policy(ICPP)is an essential manifestation of China’s construction of an innovative and green-driven development country.We incorporated urban green total factor productivity(GTFP)growth into...The innovative city pilot policy(ICPP)is an essential manifestation of China’s construction of an innovative and green-driven development country.We incorporated urban green total factor productivity(GTFP)growth into the evaluation of ICPP.Based on the panel data of 223 cities in China from 2005 to 2020,we used the difference-in-differences model to empirically assess the influence and mechanism of the ICPP on urban GTFP growth.The main results show that(i)The ICPP has maintained an effectively fluctuating promotion on urban GTFP growth,mainly manifested in the urban green technological progress improvement.(ii)The ICPP has urban heterogeneity in promoting GTFP growth in pilot cities,mainly affecting key cities such as provincial capitals.(iii)The interaction between the agglomeration of producer services and the ICPP inhibits GTFP growth in pilot cities.展开更多
This study constructs a quasi-natural experiment based on the expansion of the Yangtze River Delta urban agglomeration(YRDUA) of China in 2010 to investigate the impact and inner mechanism of urban agglomeration expan...This study constructs a quasi-natural experiment based on the expansion of the Yangtze River Delta urban agglomeration(YRDUA) of China in 2010 to investigate the impact and inner mechanism of urban agglomeration expansion on fine particulate matter(PM_(2.5)) concentrations through propensity scores in difference-in-differences models(PSM-DID) using panel data from 286 prefecturelevel cities in China from 2003 to 2016. The results show that 1) urban agglomeration expansion contributes to an overall decrease in PM_(2.5)concentration, which is mainly achieved from the original cities. For the new cities, on the other hand, the expansion significantly increases the local PM_(2.5)concentration. 2) In the long term, the significant influence of urban agglomeration expansion on PM_(2.5)concentration lasts for three years and gradually decreases. A series of robustness tests confirm the applicability of the PSM-DID model.3) Cities with weaker government regulation, a better educated population and higher per capita income present stronger PM_(2.5)reduction effects. 4) Urban agglomeration expansion affects the PM_(2.5)concentration mainly through industrial transfer and population migration, which cause a decrease in the PM_(2.5)concentration in the original cities and an increase in the PM_(2.5)concentration in the new cities.Corresponding policy suggestions are proposed based on the conclusions.展开更多
文摘The current portfolio model for property-liability insurance company is only single period that can not meet the practical demands of portfolio management, and the purpose of this paper is to develop a multiperiod model for its portfolio problem. The model is a multistage stochastic programming which considers transaction costs, cash flow between time periods, and the matching of asset and liability; it does not depend on the assumption for normality of return distribution. Additionally, an investment constraint is added. The numerical example manifests that the multiperiod model can more effectively assist the property-liability insurer to determine the optimal composition of insurance and investment portfolio and outperforms the single period one.
基金supported by the National Social Science Fund of China[Grant No.21BGL181]to Yan Chen.
文摘Coal dependence and inefficient decentralized heating have significantly increased China’s energy consumption for winter heating,increasing air pollution and exacerbating the greenhouse effect.In 2017,China implemented the Pilot Policy on Clean Winter Heating in Northern China,aiming to achieve high central heating coverage and cleaner energy consumption.Studying the effects of this policy can help promote its implementation and serve as a reference for effective adjustment of the contents in the future.However,few studies have investigated this policy and its carbon reduction effects,and most focus on the provincial or city levels.Therefore,this paper considers the policy’s influence on air pollution and carbon emissions at the county level to provide a precise and comprehensive assessment of the policy effects.We use panel data from 1290 counties in 15 provinces in Northern China from 2014 to 2021,applying a multiperiod difference-in-differences model to quantify the impact of the policy on carbon emissions and air quality in the pilot area.We then conduct a series of tests to demonstrate the robustness of the results and analyze the mechanisms of the policy effects from two perspectives,namely,central heating and natural gas use,through a mediating effect model.Finally,we examine the heterogeneity of policy effects between counties based on geographic location and per capita income levels of rural residents through a moderating effect model.The results reveal that the policy significantly reduces air pollution and carbon emissions in the pilot area by increasing the central heating area and natural gas use.Compared with the central and western regions in the north and areas with low-income rural residents,the policy effects in the eastern regions in the north and areas with high-income rural residents are more pronounced.
基金The authors declare that fund support was received from National Social Science Fund of China[Grant No.23BJL010].
文摘As urbanization accelerates globally,air pollution-particularly PM_(2.5)-is becoming an increasingly significant threat,not only to public health but also the environment.In-depth research on the impact of China’s Zero Waste City pilot policy on PM_(2.5)concentration offers valuable insights into the policy’s effectiveness and provides a potential model for environmental governance worldwide.This study employs panel data from 293 Chinese cities from 2014 to 2022 to systematically analyze the impact of the Zero-Waste City policy on PM_(2.5)concentration using a difference-in-differences model.The findings indicate that the policy not only directly reduces PM_(2.5)concentration but also indirectly curbs PM_(2.5)emissions by enhancing green innovation and green economic efficiency.Moreover,the policy’s effects are found to be positively moderated by urban energy dependence and digital financial inclusion,while they are negatively moderated by the government debt ratio.Based on these findings,this study suggests that cities should actively develop their digital economy,reduce government debt,promote green innovation,and improve green economic efficiency,as doing so will enhance their implementation of environmental policies and promote sustainable urban development.
文摘To effectively solve the problem of environmental pollution,the Chinese government has implemented an environmental supervision system since 2002.The environmental supervision system mainly uses the four functions of supervision,investigation,coordination,and emergency response to strengthen environmental protection supervision and law enforcement,respond to environmental emergencies,and coordinate cross-regional pollution disputes.As an important system design for China to control environmental pollution and promote the ecological transformation of economic development,the policy effect of the environmental supervision system deserves attention.This paper uses the difference-in-differences method to investigate the impact of the top-down environmental supervision system on air quality based on the 2000-2016 data for 285 prefecture-level cities in China.The results indicate that the annual average concentration of PM_(2.5)decreased significantly after the implementation of the environmental supervision system.The dynamic analysis shows that PM_(2.5)decreased most markedly in the first year after the implementation of the policy,and then the effect gradually weakened.Mechanism analysis suggests that the environmental supervision system can break the collusion between government and enterprise,encourage enterprises to carry out technological innovation,change pollutant discharge behavior and push local governments to adjust the industrial structure,enhance environmental protection awareness to reduce the PM_(2.5)concentration,and improve air quality.Comparing different regions,the PM_(2.5)in East China,North China and Northeast China are relatively high,and the pressure for air pollution control is great.Meanwhile,we find that the environmental supervision system has a significant station effect.Compared with other cities,the cities where the environmental supervision centers are located are more deterred by the environmental supervision,and their air quality has improved to a significantly greater degree.In the future,we should further strengthen the environmental supervision of high-pollution areas and non-station cities,and pay more attention to improving the long-term effect of the environmental supervision system.
基金Natural Science Foundation of China(Key Program,No 72133003)Key Projects of Philosophy and Social Sciences Research,Ministry of Education,(Grant No.:22JZD008).
文摘The green credit policy(GCP)is an essential financial policy tool for solving the problem of environmental pollution,and urban energy conservation is an effective way to achieve the goal of carbon neutrality.However,existing research has not verified the energy-saving effects of green credit(GC)at the city level.Based on panel data from 283 cities in China,this study aims to investigate whether GC can effectively reduce urban energy intensity(EI),which is an important complement to existing research.In terms of research methods,to better evaluate the effect of the policy and exclude the influence of other relevant factors,this study considers the promulgation of the Green Credit Guideline(GCG)in 2012 as the basic event,uses the difference-in-differences(DID)model to investigate the impact of GC on EI,and discusses the main impact mechanism.The key results are follows.(1)GC can effectively reduce urban EI.(2)Public environmental demand positively regulates the negative correlation between GC and EI.(3)GC reduces EI through three main channels:government support,capital investment,and technological innovation;however,the mechanism of industrial structure has no significant effect.(4)The effect of GC is more significant in areas with large urban scales,low environmental regulation intensity,and high industrial agglomeration.Based on the above results,this study presents puts forward targeted policy recommendations to strengthen the role of GC in urban sustainable development.
基金supported by the National Institute of Environmental Health Sciences(NIEHS)of United States(No.R00ES027511)the National Natural Science Foundation of China(No.42201303).
文摘Long-term exposure to fine particulate matters(PM_(2.5))has been associated with respiratory and cardiovascular diseases and the burden are potentially higher in China experiencing heavy air pollution.In this study,we established the exposure-response association between long-term exposures to PM_(2.5)and lung function and blood pressure in Chinesemiddle-aged and older adults using linearmixed-effects and generalized additive mixedmodels based on 3 waves longitudinal health outcomes data by enrolling 19,988 participants from 121 cities across themainland of China.We also assessed the effect of Clean Air Policy(CAP)based on a quasi-experimental difference-in-differences(DID)design.A 10μg/m^(3)increase in PM_(2.5)concentration was associated with a 7.18(95%confidence interval[CI]:-8.35,-6.02)L/min decrease in PEF(peak expiratory flow)and a 0.72(95%[CI]:0.53,0.90)and a 0.30(95%[CI]:0.18,0.42)mmHg increase in systolic and diastolic blood pressure,respectively.The associations were more pronounced in males and rural areas for PEF,but similar across subgroups for blood pressure.DID results suggested that the effect of CAP on health outcomes were sensitive tomagnitudes of reduction in PM_(2.5).A 5μg/m^(3)reduction in PM_(2.5)or more generally led to 18.70(95%[CI]:0.79,36.61)higher PEF and-2.05(95%[CI]:-3.87,-0.23)lower diastolic blood pressure,respectively,compared to no reduction or increase in exposure.However,the effects were significant only in rural areas.Our analysis support CAP aiming to benefit public health and provides insights to inform future control policy for efficiently decreasing air pollution exposure burden.
文摘As a unique environmental regulation in China,the official accountability audit was piloted in 2014.With a focus on prioritizing the ecological environment,officials in pilot districts have implemented economic construction,adjusted industrial structures,and promoted coordinated development between the economy and environment.The effects of implementation have garnered widespread attention from society.However,there is limited research on the impact of an accountability audit on industrial structure adjustments.Using the“Accountability Audit of Officials for Natural Resource Assets(Trial)”released in 2015 as a quasi-natural experiment,this study collected panel data from 279 cities between 2013 and 2017.It then empirically analyzed the impact mechanism and effects of the accountability audit on industrial structure adjustment using the Propensity Score Matching and Difference-in-Differences model.The research findings indicate that the accountability audit directly impacted industrial structure adjustment,promoting the upgrading of the primary industry to the secondary industry and restricting the development of the tertiary industry.In addition,the audit is beneficial for enterprise entry,but not conducive to technological innovation,and has no significant impact on foreign direct investment.This conclusion fills a gap in the existing research and provides valuable insights for policymakers.
基金The authors are grateful for the financial supportive from the National Natural Science Foundation of China(71473010)and(41701635).
文摘There is a worldwide consensus that excessive anthropogenic carbon dioxide emissions will lead to global warming and other environmental problems.Supports from regulations and policies have gradually implemented in this area.As one of the most discussed policies,the carbon emissions trading schemes(CETS)has an advantage in its price-oriented and cost-saving characteristics.In this paper,we analyze and assess the CETS effect from static and dynamic perspectives by applying provincial panel data covering a period ranging from 2004 to 2017.The CETS policy has a significant constraining effect on both carbon emissions and primary energy consumption.Compared to the other two uncertainties,namely the energy price uncertainty and the technology uncertainty,the carbon permit price uncertainty has a relatively smooth impact on the economy,which is being pursued consistently by the policymakers.
基金Study on the Path of Promoting the Integration of“Three Societies”and Help Rural Revitalization in Chongqing,Chongqing Social Science Planning Office[Grant number.2019WT13]Study on the Cultivation of Language Service Talents Under the Background of Belt and Road Initiative,Chongqing Social Science Planning Office[Grant number.2021WYZX12].
文摘The innovative city pilot policy(ICPP)is an essential manifestation of China’s construction of an innovative and green-driven development country.We incorporated urban green total factor productivity(GTFP)growth into the evaluation of ICPP.Based on the panel data of 223 cities in China from 2005 to 2020,we used the difference-in-differences model to empirically assess the influence and mechanism of the ICPP on urban GTFP growth.The main results show that(i)The ICPP has maintained an effectively fluctuating promotion on urban GTFP growth,mainly manifested in the urban green technological progress improvement.(ii)The ICPP has urban heterogeneity in promoting GTFP growth in pilot cities,mainly affecting key cities such as provincial capitals.(iii)The interaction between the agglomeration of producer services and the ICPP inhibits GTFP growth in pilot cities.
基金Under the auspices of Chinese National Funding of Social Sciences (No.17AGL005)Institute of Socialism with Chinese Characteristics of Southeast University (No.DDZTZK2021C11)。
文摘This study constructs a quasi-natural experiment based on the expansion of the Yangtze River Delta urban agglomeration(YRDUA) of China in 2010 to investigate the impact and inner mechanism of urban agglomeration expansion on fine particulate matter(PM_(2.5)) concentrations through propensity scores in difference-in-differences models(PSM-DID) using panel data from 286 prefecturelevel cities in China from 2003 to 2016. The results show that 1) urban agglomeration expansion contributes to an overall decrease in PM_(2.5)concentration, which is mainly achieved from the original cities. For the new cities, on the other hand, the expansion significantly increases the local PM_(2.5)concentration. 2) In the long term, the significant influence of urban agglomeration expansion on PM_(2.5)concentration lasts for three years and gradually decreases. A series of robustness tests confirm the applicability of the PSM-DID model.3) Cities with weaker government regulation, a better educated population and higher per capita income present stronger PM_(2.5)reduction effects. 4) Urban agglomeration expansion affects the PM_(2.5)concentration mainly through industrial transfer and population migration, which cause a decrease in the PM_(2.5)concentration in the original cities and an increase in the PM_(2.5)concentration in the new cities.Corresponding policy suggestions are proposed based on the conclusions.
