This paper takes global manufacturing listed companies from 2010 to 2022 as samples and uses the difference-in-differences(DID)method to empirically examine the impact of the internationalization of ESG standards on t...This paper takes global manufacturing listed companies from 2010 to 2022 as samples and uses the difference-in-differences(DID)method to empirically examine the impact of the internationalization of ESG standards on the trade competitiveness of multinational enterprises and their mechanisms.The research finds that the internationalization of ESG standards significantly enhances the trade competitiveness of multinational manufacturing enterprises,and this effect is dynamic and sustainable.The mechanism analysis indicates that the internationalization of ESG standards exerts its influence through three pathways:reducing enterprise financing costs,promoting technological innovation,and enhancing brand reputation.The heterogeneity analysis shows that this effect is more significant in enterprises from developed countries,high-pollution industries,and larger enterprises.This paper provides micro-level evidence for understanding the economic consequences of the internationalization of ESG standards and offers policy implications for multinational enterprises to cope with the global ESG rule changes and enhance their trade competitiveness.展开更多
Purpose:In recent decades,with the availability of large-scale scientific corpus datasets,difference-in-difference(DID)is increasingly used in the science of science and bibliometrics studies.DID method outputs the un...Purpose:In recent decades,with the availability of large-scale scientific corpus datasets,difference-in-difference(DID)is increasingly used in the science of science and bibliometrics studies.DID method outputs the unbiased estimation on condition that several hypotheses hold,especially the common trend assumption.In this paper,we gave a systematic demonstration of DID in the science of science,and the potential ways to improve the accuracy of DID method.Design/methodology/approach:At first,we reviewed the statistical assumptions,the model specification,and the application procedures of DID method.Second,to improve the necessary assumptions before conducting DID regression and the accuracy of estimation,we introduced some matching techniques serving as the pre-selecting step for DID design by matching control individuals who are equivalent to those treated ones on observational variables before the intervention.Lastly,we performed a case study to estimate the effects of prizewinning on the scientific performance of Nobel laureates,by comparing the yearly citation impact after the prizewinning year between Nobel laureates and their prizewinning-work coauthors.Findings:We introduced the procedures to conduct a DID estimation and demonstrated the effectiveness to use matching method to improve the results.As a case study,we found that there are no significant increases in citations for Nobel laureates compared to their prizewinning coauthors.Research limitations:This study ignored the rigorous mathematical deduction parts of DID,while focused on the practical parts.Practical implications:This work gives experimental practice and potential guidelines to use DID method in science of science and bibliometrics studies.Originality/value:This study gains insights into the usage of econometric tools in science of science.展开更多
Based on personality trait theory and experiential learning theory,lots of studies have revealed a reverse causal relationship between volunteering and the non-cognitive abilities of college students.Using data from a...Based on personality trait theory and experiential learning theory,lots of studies have revealed a reverse causal relationship between volunteering and the non-cognitive abilities of college students.Using data from a longitudinal survey of college students in Hunan Province,China,this study employed the difference-in-differences method to examine the causal relationship between volunteering and non-cognitive abilities,aiming to determine whether volunteering screens or cultivates the non-cognitive abilities of college students.The findings confirmed the screening effect of volunteering on extraversion and conscientiousness and the cultivating effect on agreeableness.However,there was neither a screening effect nor a cultivating effect on emotional stability and openness.It is indicated that volunteering during college primarily screens the non-cognitive abilities of students through personality trait mechanisms,with a limited cultivating effect on non-cognitive abilities.This highlights the necessity to prompt a re-evaluation of how volunteering fulfills its educational function.展开更多
This study proposes a regression-based estimation method in difference-in-differences settings in the presence of time-varying covariates-a scenario commonly encountered in applications.We impose only a conditional pa...This study proposes a regression-based estimation method in difference-in-differences settings in the presence of time-varying covariates-a scenario commonly encountered in applications.We impose only a conditional parallel trends assumption with timevarying covariates and plausible assumptions on the conditional expectation functions.We show that a family of causal effect parameters is exactly the coefficient estimators from our proposed regressions even in the presence of staggered treatment timing and treatment effect heterogeneity across cohorts,time periods,and covariates.These parameters can be further aggregated to the dynamic treatment effects and the overall effect of being treated.We establish the corresponding asymptotic properties.Simulation studies suggest that our proposed regression-based estimators successfully outperform in estimating the causal parameters.Finally,we apply this method to evaluate the effect of intrastate bank deregulation on income inequality in the United States in the setting of Beck et al.(2010).We find substantially different results based on our proposed method.展开更多
Environmental protection policies(EPPs)play a pivotal role in advancing sustainable development and maintaining ecological balance by establishing clear directives and standards.However,a comprehensive methodology to ...Environmental protection policies(EPPs)play a pivotal role in advancing sustainable development and maintaining ecological balance by establishing clear directives and standards.However,a comprehensive methodology to evaluate the effectiveness of these policies remains underdeveloped.Here,we employ a difference-in-differences(DID)approach to assess the effectiveness of EPPs,using the implementation of the Resident Work(RW)policy as a quasi-natural experiment.Drawing on urban-level panel data from the Yangtze River Basin between 2016 and 2021,we demonstrate that the DID model robustly evaluates the RW policy's impact on water quality improvement.Cities that adopted the RW policy experienced a 0.0098 reduction in water pollution compared to non-adopting cities.A dynamic analysis revealed progressive water quality improvements over time,with stronger effects observed in economically disadvantaged cities.Furthermore,higher policy evaluation scores correlated with greater improvements in water quality.This study highlights the utility of the DID model in quantifying EPP effectiveness and offers a scalable framework for policy evaluation in environmental management.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
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
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
Drawing on local legitimacy theory,which posits that firms seek acceptance and approval from their local community and stakeholders,we examine the effect of corporate governance(CG)quality on corporate social responsi...Drawing on local legitimacy theory,which posits that firms seek acceptance and approval from their local community and stakeholders,we examine the effect of corporate governance(CG)quality on corporate social responsibility(CSR)activities in Korea.Enhancing CG quality and engaging in CSR activities are increasingly important for firms’long-term sustainability.Using the KEJI-CSR index and the KCGS CG score,we find that CG quality positively influences CSR activities.Specifically,if the CG quality score increases by one standard deviation,CSR improves by approximately 1.6–2.3%of the mean CSR score.Furthermore,the relationship between CG and CSR is stronger for business conglomerates(chaebol-affiliated firms),suggesting that sound CG practices can promote CSR activities more effectively when the interests of management and stakeholders are better aligned.This finding supports local legitimacy theory.Our findings are robust under various tests,including difference-in-differences analysis and propensity score matching.An interesting policy implication is that multinational enterprises or foreign investors should prioritize the CG quality of their local subsidiaries or investee firms.Better CG practices can enhance CSR activities,which are essential for long-term survival in local markets.This study,however,is limited to Korea and may not be generalizable to other emerging markets with different governance structures.展开更多
Amid growing global attention to low-carbon transitions,the environmental effects of rural tourism remain theoretically underexplored.Drawing on Ecological Modernization Theory(EMT),this study examines whether and how...Amid growing global attention to low-carbon transitions,the environmental effects of rural tourism remain theoretically underexplored.Drawing on Ecological Modernization Theory(EMT),this study examines whether and how rural tourism contributes to carbon emission reduction in China.Using a quasi-natural experiment based on the designation of National Demonstration Counties for Rural Tourism,we construct panel data for 273 cities from 2006 to 2022 and employ a difference-in-differences model to identify causal effects.Results show that rural tourism significantly reduces carbon emissions,particularly through three mechanisms:improved digital infrastructure,enhanced technological innovation,and greater adoption of clean energy.Heterogeneity analysis reveals stronger effects in eastern regions,non-tourism-dominated cities,and areas with rich tourism resources.This study contributes to the literature by extending EMT into rural service economies,proposing a multi-pathway framework for understanding tourism-driven decarbonization,and providing empirical insights into the role of tourism in national climate strategies.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
This paper focuses on Chengdu and Chongqing’s positioning as important economic center in western China and their evolving into an economic center of national influence.On the one hand,it uses the synthetic differenc...This paper focuses on Chengdu and Chongqing’s positioning as important economic center in western China and their evolving into an economic center of national influence.On the one hand,it uses the synthetic difference-in-differences(SDID)method to analyze the impact of policies since 2011 designed to build Chengdu and Chongqing into an important economic center in western China.On the other hand,it employs the entropy-weighted TOPSIS method to comprehensively evaluate the influences of ten core Chinese cities as economic centers within four major urban agglomerations,as well as conduct an analytical assessment of the Chengdu-Chongqing economic circle from key perspectives such as its capacity to lead,capacity to agglomerate,and capacity to radiate.From a longitudinal historical perspective,both Chengdu and Chongqing have benefited significantly from policies designed to build an important economic center in western China,and which laid a foundation for building an economic center of national influence.From a horizontal regional comparison,among the ten core cities evaluated as economic centers within the four major urban agglomerations,Chengdu and Chongqing ranked in the middle,possessing a moderate but not yet outstanding influence.Consequently,to evolve into an economic center of national influence,the Chengdu-Chongqing economic circle should leverage its relative advantages in connectivity,market size,value chain division of labor,policy attractiveness,and industry development.It can enhance its influence by strengthening the complementarity of its economic resources,overcoming the administrative inertia,accelerating the establishment of a regional innovation system,broadening the scope of its economic radiation,and promoting its comprehensive and all-dimensional opening-up.展开更多
This paper leverages the Opinions of the State Council on Further Promoting the Reform of the Household Registration System as a quasi-natural experiment to examine the impact of rural migrant urbanization on local go...This paper leverages the Opinions of the State Council on Further Promoting the Reform of the Household Registration System as a quasi-natural experiment to examine the impact of rural migrant urbanization on local government expenditures in science and technology(S&T)and education.Employing a generalized difference-in-differences(generalized-DID)approach and panel data from 271 Chinese prefecture-level and above-level cities spanning 2003–2019,we find that household registration reform driven by this urbanization process significantly increased the absolute level as well as the fiscal share of S&T and education spending.Mechanism analyses indicate that rural migrant urbanization promotes these expenditures through two channels:increasing the overall local fiscal revenue and encouraging a greater proportion of the fiscal resources to be allocated to these sectors.The findings uncover the current evolving trends in fiscal resource allocation due to rural migrant urbanization and provide empirical evidence for optimizing the provision of public services and enhancing the potential of long-term economic development.展开更多
Amid China’s rapid economic growth,significant regional imbalances persisted.To address this disparity,it is essential to pursue high-quality development by fostering endogenous drivers within poverty-stricken areas....Amid China’s rapid economic growth,significant regional imbalances persisted.To address this disparity,it is essential to pursue high-quality development by fostering endogenous drivers within poverty-stricken areas.In late 2011,the Chinese government introduced a new nationwide regional poverty alleviation and development program.This study examines the macroeconomic impacts and micro-level mechanisms of these policies by leveraging manually compiled policy documents and macro and micro data(county economies,enterprises,and land transactions),using a DID approach.The findings reveal that the program significantly boosted economic growth in poor regions without causing negative spillovers to neighboring or paired-assistance areas.Economic growth in the assisted regions was primarily driven by industrialization,encompassing both scale expansion and efficiency gains.A cost-benefit analysis further confirms substantial economic returns and long-term fiscal sustainability.These results provide important policy implications for refining regional poverty policies and advancing balanced development.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
Using data from the 11th to 14th Five-Year Plan periods(2006-2025),this study applies a Difference-in-Differences(DID)approach to assess the impact of industrial policy withdrawal.Industries that have faced policy wit...Using data from the 11th to 14th Five-Year Plan periods(2006-2025),this study applies a Difference-in-Differences(DID)approach to assess the impact of industrial policy withdrawal.Industries that have faced policy withdrawal for over a decade are categorized as the treatment group,while consistently supported industries form the control group.The analysis examines how withdrawal affects firm total factor productivity(TFP)and investment behavior.The results show that policy withdrawal boosts firm TFP by reducing over-investment and improving the efficiency of R&D spending.This effect is particularly evident in industries with strong,competitive leading firms.Additionally,in regions with lower levels of marketization,timely policy withdrawal plays a key role in curbing over-investment.This study also highlights a dual effect of policy withdrawal:while it fosters corporate social responsibility,it may also encourage financial speculation.These findings suggest that the implementation of industrial policy should provide“timely assistance”over a limited timeframe rather than long-term support to well-established industries.As industries mature,policy support should be gradually reduced or phased out to avoid over-investment and enhance firm efficiency.展开更多
Beginning in 1997, China implemented a six-round campaign to accelerate train service, known as the ＂ China Railway Speed-Up Campaign＇＂ which greatly increased railway capacity and improved the quality of rail faci...Beginning in 1997, China implemented a six-round campaign to accelerate train service, known as the ＂ China Railway Speed-Up Campaign＇＂ which greatly increased railway capacity and improved the quality of rail facilities. This can be seen as a natural experiment of the effects of improving the quality of transportation infrastructure. Using the Beijing- Guangzhou Line and the Beijing-Shanghai Line as examples, this paper creates city-level panel data for stations along accelerated lines and traditional stations for the years between 1994 and 2006 and systematically examines the campaign＇s effect on economic growth using difference-in-difference （DID） methodology. Our research concludes that railway acceleration has promoted economic growth in cities with stations on upgraded rail lines. Over the entire period of the speed-up campaign, the per capita GDP growth rate has risen by 3.7percentage points in cities with upgraded stations versus cities with traditional stations. Moreover, positive effects on economic growth have been found to increase in later stages of railway upgrades.展开更多
为抑制房地产价格过快上涨,房地产价格调控新政(新国五条)和各地细则于2013年4月1日开始执行。本文基于Web Data Mining技术,利用SAS软件获取了新国五条政策执行前一期以及政策执行后三期京津地区170个小区的二手房屋挂牌价格及相关因...为抑制房地产价格过快上涨,房地产价格调控新政(新国五条)和各地细则于2013年4月1日开始执行。本文基于Web Data Mining技术,利用SAS软件获取了新国五条政策执行前一期以及政策执行后三期京津地区170个小区的二手房屋挂牌价格及相关因素数据。根据改进的倍差法(Difference-in-Difference)模型,对以上数据进行分析,得出了政策对于总体房屋价格的差异,不仅如此,我们还对与不同特性二手房屋价格受到的不同政策影响进行了计量分析。得出了结论:北京新国五条新政对于房屋价格整体有正的影响,促进了北京二手房挂牌价格提升,并且对于学区房和地铁通达性较好的二手房挂牌价格有额外的正的影响,而对于满五年住房挂牌价格影响并不显著。并且进一步的提出了政策建议。展开更多
Food security is a strategic priority for a country’s economic development.In China,high-standard farmland construction(HSFC)is an important initiative to stabilize grain production and increase grain production capa...Food security is a strategic priority for a country’s economic development.In China,high-standard farmland construction(HSFC)is an important initiative to stabilize grain production and increase grain production capacity.Based on panel data from 31 sample provinces,autonomous regions,and municipalities in China from 2005–2017,this study explored the impact of HSFC on grain yield using the difference-in-differences(DID)method.The results showed that HSFC significantly increased total grain production,which is robust to various checks.HSFC increased grain yield through three potential mechanisms.First,it could increase the grain replanting index.Second,it could effectively reduce yield loss due to droughts and floods.Last,HSFC could strengthen the cultivated land by renovating the low-and medium-yielding fields.Heterogeneity analysis found that the HSFC farmland showed a significant increase in grain yield only in the main grain-producing areas and balanced areas.In addition,HSFC significantly increased the yields of rice,wheat,and maize while leading to a reduction in soybean yields.The findings suggest the government should continue to promote HSFC,improve construction standards,and strictly control the“non-agriculturalization”and“non-coordination”of farmland to increase grain production further.At the same time,market mechanisms should be used to incentivize soybean farming,improve returns and stabilize soybean yields.展开更多
The wheat canopy reflectance spectrum is affected by many internal and external factors such as diseases and growth stage. Separating the effects of disease stress on the crop from the observed mixed signals is crucia...The wheat canopy reflectance spectrum is affected by many internal and external factors such as diseases and growth stage. Separating the effects of disease stress on the crop from the observed mixed signals is crucial for increasing the precision of remote sensing monitoring of wheat stripe rust. The canopy spectrum of winter wheat infected by stripe rust was processed with the difference-in-differences(DID) algorithm used in econometrics. The monitoring accuracies of wheat stripe rust before and after processing with the DID algorithm were compared in the presence of various external factors, disease severity, and several simulated satellite sensors. The correlation between the normalized difference vegetation index processed by the DID algorithm(NDVI-DID) and the disease severity level(SL) increased in comparison with the NDVI before processing. The increase in precision in the natural disease area in the field in the presence of large differences in growth stage, growth, planting, and management of the crop was greater than that in the controlled experiment. For low disease levels(SL < 20%), the R2 of the regression of NDVI-DIDon SL was 38.8% higher than that of the NDVI and the root mean square error(RMSE) was reduced by 11.1%. The increase in precision was greater than that for the severe level(SL > 40%).According to the measured hyperspectral data, the spectral reflectance of three satellite sensor levels was simulated. The wide-band NDVI was calculated. Compared with the wide-band NDVI and vegetation indexes(VI) before DID processing, there were increases in the correlation between SL and the various types of VIS-DID, as well as in the correlation between SL and NDVI-DID. It is feasible to apply the DID algorithm to multispectral satellite data and diverse types of VISfor monitoring wheat stripe rust. Our results improve the quantification of independent effects of stripe rust infection on canopy reflectance spectrum,increase the precision of remote sensing monitoring of wheat stripe rust, and provide a reference for remote sensing monitoring of other crop diseases.展开更多
文摘This paper takes global manufacturing listed companies from 2010 to 2022 as samples and uses the difference-in-differences(DID)method to empirically examine the impact of the internationalization of ESG standards on the trade competitiveness of multinational enterprises and their mechanisms.The research finds that the internationalization of ESG standards significantly enhances the trade competitiveness of multinational manufacturing enterprises,and this effect is dynamic and sustainable.The mechanism analysis indicates that the internationalization of ESG standards exerts its influence through three pathways:reducing enterprise financing costs,promoting technological innovation,and enhancing brand reputation.The heterogeneity analysis shows that this effect is more significant in enterprises from developed countries,high-pollution industries,and larger enterprises.This paper provides micro-level evidence for understanding the economic consequences of the internationalization of ESG standards and offers policy implications for multinational enterprises to cope with the global ESG rule changes and enhance their trade competitiveness.
基金This work was supported by grants from the National Natural Science Foundation of China,with No.NSFC62006109 and NSFC12031005.
文摘Purpose:In recent decades,with the availability of large-scale scientific corpus datasets,difference-in-difference(DID)is increasingly used in the science of science and bibliometrics studies.DID method outputs the unbiased estimation on condition that several hypotheses hold,especially the common trend assumption.In this paper,we gave a systematic demonstration of DID in the science of science,and the potential ways to improve the accuracy of DID method.Design/methodology/approach:At first,we reviewed the statistical assumptions,the model specification,and the application procedures of DID method.Second,to improve the necessary assumptions before conducting DID regression and the accuracy of estimation,we introduced some matching techniques serving as the pre-selecting step for DID design by matching control individuals who are equivalent to those treated ones on observational variables before the intervention.Lastly,we performed a case study to estimate the effects of prizewinning on the scientific performance of Nobel laureates,by comparing the yearly citation impact after the prizewinning year between Nobel laureates and their prizewinning-work coauthors.Findings:We introduced the procedures to conduct a DID estimation and demonstrated the effectiveness to use matching method to improve the results.As a case study,we found that there are no significant increases in citations for Nobel laureates compared to their prizewinning coauthors.Research limitations:This study ignored the rigorous mathematical deduction parts of DID,while focused on the practical parts.Practical implications:This work gives experimental practice and potential guidelines to use DID method in science of science and bibliometrics studies.Originality/value:This study gains insights into the usage of econometric tools in science of science.
文摘Based on personality trait theory and experiential learning theory,lots of studies have revealed a reverse causal relationship between volunteering and the non-cognitive abilities of college students.Using data from a longitudinal survey of college students in Hunan Province,China,this study employed the difference-in-differences method to examine the causal relationship between volunteering and non-cognitive abilities,aiming to determine whether volunteering screens or cultivates the non-cognitive abilities of college students.The findings confirmed the screening effect of volunteering on extraversion and conscientiousness and the cultivating effect on agreeableness.However,there was neither a screening effect nor a cultivating effect on emotional stability and openness.It is indicated that volunteering during college primarily screens the non-cognitive abilities of students through personality trait mechanisms,with a limited cultivating effect on non-cognitive abilities.This highlights the necessity to prompt a re-evaluation of how volunteering fulfills its educational function.
基金supported by the Special Project for Training Young Science and Technology Talents in Early Career Development of Jiangxi Province,China(Grant No.20244BCE52087).
文摘This study proposes a regression-based estimation method in difference-in-differences settings in the presence of time-varying covariates-a scenario commonly encountered in applications.We impose only a conditional parallel trends assumption with timevarying covariates and plausible assumptions on the conditional expectation functions.We show that a family of causal effect parameters is exactly the coefficient estimators from our proposed regressions even in the presence of staggered treatment timing and treatment effect heterogeneity across cohorts,time periods,and covariates.These parameters can be further aggregated to the dynamic treatment effects and the overall effect of being treated.We establish the corresponding asymptotic properties.Simulation studies suggest that our proposed regression-based estimators successfully outperform in estimating the causal parameters.Finally,we apply this method to evaluate the effect of intrastate bank deregulation on income inequality in the United States in the setting of Beck et al.(2010).We find substantially different results based on our proposed method.
基金supported by The Yangtze River Joint Research Phase Ⅱ Program(No.2022-LHYJ-02-0402).
文摘Environmental protection policies(EPPs)play a pivotal role in advancing sustainable development and maintaining ecological balance by establishing clear directives and standards.However,a comprehensive methodology to evaluate the effectiveness of these policies remains underdeveloped.Here,we employ a difference-in-differences(DID)approach to assess the effectiveness of EPPs,using the implementation of the Resident Work(RW)policy as a quasi-natural experiment.Drawing on urban-level panel data from the Yangtze River Basin between 2016 and 2021,we demonstrate that the DID model robustly evaluates the RW policy's impact on water quality improvement.Cities that adopted the RW policy experienced a 0.0098 reduction in water pollution compared to non-adopting cities.A dynamic analysis revealed progressive water quality improvements over time,with stronger effects observed in economically disadvantaged cities.Furthermore,higher policy evaluation scores correlated with greater improvements in water quality.This study highlights the utility of the DID model in quantifying EPP effectiveness and offers a scalable framework for policy evaluation in environmental management.
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.
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Drawing on local legitimacy theory,which posits that firms seek acceptance and approval from their local community and stakeholders,we examine the effect of corporate governance(CG)quality on corporate social responsibility(CSR)activities in Korea.Enhancing CG quality and engaging in CSR activities are increasingly important for firms’long-term sustainability.Using the KEJI-CSR index and the KCGS CG score,we find that CG quality positively influences CSR activities.Specifically,if the CG quality score increases by one standard deviation,CSR improves by approximately 1.6–2.3%of the mean CSR score.Furthermore,the relationship between CG and CSR is stronger for business conglomerates(chaebol-affiliated firms),suggesting that sound CG practices can promote CSR activities more effectively when the interests of management and stakeholders are better aligned.This finding supports local legitimacy theory.Our findings are robust under various tests,including difference-in-differences analysis and propensity score matching.An interesting policy implication is that multinational enterprises or foreign investors should prioritize the CG quality of their local subsidiaries or investee firms.Better CG practices can enhance CSR activities,which are essential for long-term survival in local markets.This study,however,is limited to Korea and may not be generalizable to other emerging markets with different governance structures.
基金supported by the National Social Science Fund of China(Grant No.23BJY142).
文摘Amid growing global attention to low-carbon transitions,the environmental effects of rural tourism remain theoretically underexplored.Drawing on Ecological Modernization Theory(EMT),this study examines whether and how rural tourism contributes to carbon emission reduction in China.Using a quasi-natural experiment based on the designation of National Demonstration Counties for Rural Tourism,we construct panel data for 273 cities from 2006 to 2022 and employ a difference-in-differences model to identify causal effects.Results show that rural tourism significantly reduces carbon emissions,particularly through three mechanisms:improved digital infrastructure,enhanced technological innovation,and greater adoption of clean energy.Heterogeneity analysis reveals stronger effects in eastern regions,non-tourism-dominated cities,and areas with rich tourism resources.This study contributes to the literature by extending EMT into rural service economies,proposing a multi-pathway framework for understanding tourism-driven decarbonization,and providing empirical insights into the role of tourism in national climate strategies.
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.
文摘This paper focuses on Chengdu and Chongqing’s positioning as important economic center in western China and their evolving into an economic center of national influence.On the one hand,it uses the synthetic difference-in-differences(SDID)method to analyze the impact of policies since 2011 designed to build Chengdu and Chongqing into an important economic center in western China.On the other hand,it employs the entropy-weighted TOPSIS method to comprehensively evaluate the influences of ten core Chinese cities as economic centers within four major urban agglomerations,as well as conduct an analytical assessment of the Chengdu-Chongqing economic circle from key perspectives such as its capacity to lead,capacity to agglomerate,and capacity to radiate.From a longitudinal historical perspective,both Chengdu and Chongqing have benefited significantly from policies designed to build an important economic center in western China,and which laid a foundation for building an economic center of national influence.From a horizontal regional comparison,among the ten core cities evaluated as economic centers within the four major urban agglomerations,Chengdu and Chongqing ranked in the middle,possessing a moderate but not yet outstanding influence.Consequently,to evolve into an economic center of national influence,the Chengdu-Chongqing economic circle should leverage its relative advantages in connectivity,market size,value chain division of labor,policy attractiveness,and industry development.It can enhance its influence by strengthening the complementarity of its economic resources,overcoming the administrative inertia,accelerating the establishment of a regional innovation system,broadening the scope of its economic radiation,and promoting its comprehensive and all-dimensional opening-up.
基金supported by the National Natural Science Foundation of China Youth Project“Research on the Mechanism and Policy Design of the Impact of Rural Migrant Urbanization on Local Government Education Investment”(Grant No.72103034)the Distinguished Young Scholar Funding Project of the University of International Business and Economics(Grant No.21JQ11).
文摘This paper leverages the Opinions of the State Council on Further Promoting the Reform of the Household Registration System as a quasi-natural experiment to examine the impact of rural migrant urbanization on local government expenditures in science and technology(S&T)and education.Employing a generalized difference-in-differences(generalized-DID)approach and panel data from 271 Chinese prefecture-level and above-level cities spanning 2003–2019,we find that household registration reform driven by this urbanization process significantly increased the absolute level as well as the fiscal share of S&T and education spending.Mechanism analyses indicate that rural migrant urbanization promotes these expenditures through two channels:increasing the overall local fiscal revenue and encouraging a greater proportion of the fiscal resources to be allocated to these sectors.The findings uncover the current evolving trends in fiscal resource allocation due to rural migrant urbanization and provide empirical evidence for optimizing the provision of public services and enhancing the potential of long-term economic development.
基金Supported by the National Natural Science Foundation of China(NSFC)(Grant No.72173131)for“Research on New Trends and Driving Forces in China’s Labor Income Share:A Micro Perspective Based on Enterprise Behavior”the China Postdoctoral Science Foundation(Grant No.2023M743940)for“Research on the Income Distribution Effects of Transport Infrastructure Construction:Theoretical Analysis and Quantitative Assessment”.
文摘Amid China’s rapid economic growth,significant regional imbalances persisted.To address this disparity,it is essential to pursue high-quality development by fostering endogenous drivers within poverty-stricken areas.In late 2011,the Chinese government introduced a new nationwide regional poverty alleviation and development program.This study examines the macroeconomic impacts and micro-level mechanisms of these policies by leveraging manually compiled policy documents and macro and micro data(county economies,enterprises,and land transactions),using a DID approach.The findings reveal that the program significantly boosted economic growth in poor regions without causing negative spillovers to neighboring or paired-assistance areas.Economic growth in the assisted regions was primarily driven by industrialization,encompassing both scale expansion and efficiency gains.A cost-benefit analysis further confirms substantial economic returns and long-term fiscal sustainability.These results provide important policy implications for refining regional poverty policies and advancing balanced development.
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supported by the Major Project of the Beijing Social Science Fund“Research on Constructing a New Development Pattern and the Coordinated Development of the Beijing-Tianjin-Hebei Region”(20ZDA31).
文摘Using data from the 11th to 14th Five-Year Plan periods(2006-2025),this study applies a Difference-in-Differences(DID)approach to assess the impact of industrial policy withdrawal.Industries that have faced policy withdrawal for over a decade are categorized as the treatment group,while consistently supported industries form the control group.The analysis examines how withdrawal affects firm total factor productivity(TFP)and investment behavior.The results show that policy withdrawal boosts firm TFP by reducing over-investment and improving the efficiency of R&D spending.This effect is particularly evident in industries with strong,competitive leading firms.Additionally,in regions with lower levels of marketization,timely policy withdrawal plays a key role in curbing over-investment.This study also highlights a dual effect of policy withdrawal:while it fosters corporate social responsibility,it may also encourage financial speculation.These findings suggest that the implementation of industrial policy should provide“timely assistance”over a limited timeframe rather than long-term support to well-established industries.As industries mature,policy support should be gradually reduced or phased out to avoid over-investment and enhance firm efficiency.
文摘Beginning in 1997, China implemented a six-round campaign to accelerate train service, known as the ＂ China Railway Speed-Up Campaign＇＂ which greatly increased railway capacity and improved the quality of rail facilities. This can be seen as a natural experiment of the effects of improving the quality of transportation infrastructure. Using the Beijing- Guangzhou Line and the Beijing-Shanghai Line as examples, this paper creates city-level panel data for stations along accelerated lines and traditional stations for the years between 1994 and 2006 and systematically examines the campaign＇s effect on economic growth using difference-in-difference （DID） methodology. Our research concludes that railway acceleration has promoted economic growth in cities with stations on upgraded rail lines. Over the entire period of the speed-up campaign, the per capita GDP growth rate has risen by 3.7percentage points in cities with upgraded stations versus cities with traditional stations. Moreover, positive effects on economic growth have been found to increase in later stages of railway upgrades.
文摘为抑制房地产价格过快上涨,房地产价格调控新政(新国五条)和各地细则于2013年4月1日开始执行。本文基于Web Data Mining技术,利用SAS软件获取了新国五条政策执行前一期以及政策执行后三期京津地区170个小区的二手房屋挂牌价格及相关因素数据。根据改进的倍差法(Difference-in-Difference)模型,对以上数据进行分析,得出了政策对于总体房屋价格的差异,不仅如此,我们还对与不同特性二手房屋价格受到的不同政策影响进行了计量分析。得出了结论:北京新国五条新政对于房屋价格整体有正的影响,促进了北京二手房挂牌价格提升,并且对于学区房和地铁通达性较好的二手房挂牌价格有额外的正的影响,而对于满五年住房挂牌价格影响并不显著。并且进一步的提出了政策建议。
基金supported by the National Natural Science Foundation of China(41871184)the National Social Science Fund of China(21ZDA056)the Scientific and Technological Innovation Project of the Chinese Academy of Agricultural Sciences(10-IAED-ZT-01-2023and 10-IAED-RC-07-2023)。
文摘Food security is a strategic priority for a country’s economic development.In China,high-standard farmland construction(HSFC)is an important initiative to stabilize grain production and increase grain production capacity.Based on panel data from 31 sample provinces,autonomous regions,and municipalities in China from 2005–2017,this study explored the impact of HSFC on grain yield using the difference-in-differences(DID)method.The results showed that HSFC significantly increased total grain production,which is robust to various checks.HSFC increased grain yield through three potential mechanisms.First,it could increase the grain replanting index.Second,it could effectively reduce yield loss due to droughts and floods.Last,HSFC could strengthen the cultivated land by renovating the low-and medium-yielding fields.Heterogeneity analysis found that the HSFC farmland showed a significant increase in grain yield only in the main grain-producing areas and balanced areas.In addition,HSFC significantly increased the yields of rice,wheat,and maize while leading to a reduction in soybean yields.The findings suggest the government should continue to promote HSFC,improve construction standards,and strictly control the“non-agriculturalization”and“non-coordination”of farmland to increase grain production further.At the same time,market mechanisms should be used to incentivize soybean farming,improve returns and stabilize soybean yields.
基金supported by the National Natural Science Foundation of China (42171394, 41601467)。
文摘The wheat canopy reflectance spectrum is affected by many internal and external factors such as diseases and growth stage. Separating the effects of disease stress on the crop from the observed mixed signals is crucial for increasing the precision of remote sensing monitoring of wheat stripe rust. The canopy spectrum of winter wheat infected by stripe rust was processed with the difference-in-differences(DID) algorithm used in econometrics. The monitoring accuracies of wheat stripe rust before and after processing with the DID algorithm were compared in the presence of various external factors, disease severity, and several simulated satellite sensors. The correlation between the normalized difference vegetation index processed by the DID algorithm(NDVI-DID) and the disease severity level(SL) increased in comparison with the NDVI before processing. The increase in precision in the natural disease area in the field in the presence of large differences in growth stage, growth, planting, and management of the crop was greater than that in the controlled experiment. For low disease levels(SL < 20%), the R2 of the regression of NDVI-DIDon SL was 38.8% higher than that of the NDVI and the root mean square error(RMSE) was reduced by 11.1%. The increase in precision was greater than that for the severe level(SL > 40%).According to the measured hyperspectral data, the spectral reflectance of three satellite sensor levels was simulated. The wide-band NDVI was calculated. Compared with the wide-band NDVI and vegetation indexes(VI) before DID processing, there were increases in the correlation between SL and the various types of VIS-DID, as well as in the correlation between SL and NDVI-DID. It is feasible to apply the DID algorithm to multispectral satellite data and diverse types of VISfor monitoring wheat stripe rust. Our results improve the quantification of independent effects of stripe rust infection on canopy reflectance spectrum,increase the precision of remote sensing monitoring of wheat stripe rust, and provide a reference for remote sensing monitoring of other crop diseases.
