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
This paper investigates whether environmental regulation affects firm's performance including productivity,wage and employment using firm-level data in 1996-2007.The identification uses Two Control Zones(TCZ)polic...This paper investigates whether environmental regulation affects firm's performance including productivity,wage and employment using firm-level data in 1996-2007.The identification uses Two Control Zones(TCZ)policy implemented by the Chinese government in 1998,in which tougher environmental regulations were imposed in TCZ cities but not others.By difference-indifferences estimation,we find that tougher environmental regulation leads to larger increase on both total factor productivity and wage,and firms tend to employ fewer workers under pressure of environmental protection.Heterogeneous tests show that the impacts are better for nonpollution intensive firms,non-exporters and SOEs.Finally,we find that R&D input and exiting firms among industry are the driving forces for enhancing TFP and increasing wage and unemployment.展开更多
Administrative regions are an important environment for the operation of China's market economy.The relevant economic subjects cannot predict the policy of adjustment of administrative divisions and carry out cons...Administrative regions are an important environment for the operation of China's market economy.The relevant economic subjects cannot predict the policy of adjustment of administrative divisions and carry out conscious migration behavior,adjustment of administrative divisions can be regarded as a quasi-natural experiment.The three cities of Hefei,Wuhu,and Ma'anshan,which are directly related to the adjustment of the administrative division of Chaohu,are taken as the treatment group,and the seven adjacent cities of Lu'an,Huainan,Chuzhou,Bengbu,Anqing,Chizhou,and Tongling are taken as the control group.Differences-in-Differences method and relevant control variables affecting the upgrading of industrial structure are used to test.The test results show that"Partitions of Chaohu"has a significant industrial structure upgrading effect by promoting the optimization of spatial layout,the cross-regional flow of production factors and the effective management of Chaohu Lake Basin.At the same time,the increase of total retail sales of consumer goods,urban fixed assets investment,public utility expenses in science,education,culture and health,and population plays a significant positive role in promoting the upgrading of industrial structure,while foreign direct investment plays a certain inhibition role in the upgrading of industrial structure.In order to meet the ever-developing space demands and enhance the impact on surrounding areas,the Hefei metropolitan area should be driven by technological innovation,strengthen the integration of industrial chains,improve the business environment and transportation network,and continuously promote the upgrading of industrial structure and the formation and development of new productive forces.展开更多
Short selling may accelerate stock price adjustment to negative news.However,the literature provides mixed evidence for this prediction.Using short-sale refinancing and a staggered difference-in-differences(DID)model,...Short selling may accelerate stock price adjustment to negative news.However,the literature provides mixed evidence for this prediction.Using short-sale refinancing and a staggered difference-in-differences(DID)model,this paper explores the effect of short selling on stock price adjustment.Our results show that(1)short-sale refinancing improves the speed of stock price adjustment to negative news.This result holds after we control for endogeneity.(2)The positive relationship between short-sale refinancing and stock price adjustment speed is significant in subsamples of stocks with higher earnings management or lower accuracy of analyst forecasts,indicating that firms with more opaque information are more likely to be targeted by short sellers.In subsamples of stocks with a higher ownership concentration or lower ownership by institutional investors,short selling is more likely to increase the speed of stock price adjustment,indicating that ownership structure may influence negative news mining.(3)As short-sale refinancing exacerbates the absorption of bad news by stock prices,it increases crash risk.This study enriches the research on the economic consequences of short selling and provides empirical evidence supporting regulations on short selling in China.展开更多
CIRC is short for Cooperative Integrated Reading and Composition.It is to help improve students' English proficiency by integrating writing into reading.In order to verify the results of the method,the author made...CIRC is short for Cooperative Integrated Reading and Composition.It is to help improve students' English proficiency by integrating writing into reading.In order to verify the results of the method,the author made an experimental study in Nanning College for Vocational Technology.She designed a small teaching cycle of "7 phases with 12 steps"and applied CIRC in her English class.One of the results is that CIRC can improve students'academic achievements.展开更多
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.
基金The authors are supported financially by the National Natural Science Foundation of China[Grant Number.71403216,71703128,71832012]MOE(Ministry of Education of China)of Humanities and Social Sciences Project[Grant Number.19YJC790062].
文摘This paper investigates whether environmental regulation affects firm's performance including productivity,wage and employment using firm-level data in 1996-2007.The identification uses Two Control Zones(TCZ)policy implemented by the Chinese government in 1998,in which tougher environmental regulations were imposed in TCZ cities but not others.By difference-indifferences estimation,we find that tougher environmental regulation leads to larger increase on both total factor productivity and wage,and firms tend to employ fewer workers under pressure of environmental protection.Heterogeneous tests show that the impacts are better for nonpollution intensive firms,non-exporters and SOEs.Finally,we find that R&D input and exiting firms among industry are the driving forces for enhancing TFP and increasing wage and unemployment.
文摘Administrative regions are an important environment for the operation of China's market economy.The relevant economic subjects cannot predict the policy of adjustment of administrative divisions and carry out conscious migration behavior,adjustment of administrative divisions can be regarded as a quasi-natural experiment.The three cities of Hefei,Wuhu,and Ma'anshan,which are directly related to the adjustment of the administrative division of Chaohu,are taken as the treatment group,and the seven adjacent cities of Lu'an,Huainan,Chuzhou,Bengbu,Anqing,Chizhou,and Tongling are taken as the control group.Differences-in-Differences method and relevant control variables affecting the upgrading of industrial structure are used to test.The test results show that"Partitions of Chaohu"has a significant industrial structure upgrading effect by promoting the optimization of spatial layout,the cross-regional flow of production factors and the effective management of Chaohu Lake Basin.At the same time,the increase of total retail sales of consumer goods,urban fixed assets investment,public utility expenses in science,education,culture and health,and population plays a significant positive role in promoting the upgrading of industrial structure,while foreign direct investment plays a certain inhibition role in the upgrading of industrial structure.In order to meet the ever-developing space demands and enhance the impact on surrounding areas,the Hefei metropolitan area should be driven by technological innovation,strengthen the integration of industrial chains,improve the business environment and transportation network,and continuously promote the upgrading of industrial structure and the formation and development of new productive forces.
基金the financial support from the National Natural Science Foundation of China(No.71802078)the Fundamental Funds for the Central Universities(No.531107051035).
文摘Short selling may accelerate stock price adjustment to negative news.However,the literature provides mixed evidence for this prediction.Using short-sale refinancing and a staggered difference-in-differences(DID)model,this paper explores the effect of short selling on stock price adjustment.Our results show that(1)short-sale refinancing improves the speed of stock price adjustment to negative news.This result holds after we control for endogeneity.(2)The positive relationship between short-sale refinancing and stock price adjustment speed is significant in subsamples of stocks with higher earnings management or lower accuracy of analyst forecasts,indicating that firms with more opaque information are more likely to be targeted by short sellers.In subsamples of stocks with a higher ownership concentration or lower ownership by institutional investors,short selling is more likely to increase the speed of stock price adjustment,indicating that ownership structure may influence negative news mining.(3)As short-sale refinancing exacerbates the absorption of bad news by stock prices,it increases crash risk.This study enriches the research on the economic consequences of short selling and provides empirical evidence supporting regulations on short selling in China.
文摘CIRC is short for Cooperative Integrated Reading and Composition.It is to help improve students' English proficiency by integrating writing into reading.In order to verify the results of the method,the author made an experimental study in Nanning College for Vocational Technology.She designed a small teaching cycle of "7 phases with 12 steps"and applied CIRC in her English class.One of the results is that CIRC can improve students'academic achievements.