A dynamic panel data approach and HCW's method:Assessing the effect of China(Shanghai)Free Trade Zone on local GDP

We propose a simple-to-implement dynamic panel data method to evaluate the impacts of place-based policies.The idea is to exploit both the cross sectional dependence and the serial correlation within a panel and implement a semi difference-in-difference decomposition.Different from the method by Hsiao et al.(2012),the proposed model is easy to implement statistical inferences and can incorporate multiple treated groups at different time thresholds.We use the proposed method to explore the effect of the Free Trade Zone(FTZ)policy implemented in Shanghai at the end of 2013 on local GDP growth rate and compare it with that from Hsiao et al.(2012).The empirical results show that the FTZ does have a positive effect on the local GDP growth rate and it adds 1:21:8 percent point to the growth rate of the GDP per capita for Shanghai in 2014 which is about one fourth to one third of the total GDP growth rate per capita.This effect largely comes from the growth of the tertiary sector.The results lend support to the duplication of FTZ policy to other cities and provinces in China.

Grain Science and Technology Policies and Food Security in China:An Empirical Study Based on a Provincial Dynamic Panel Model

China’s grain science and technology policies have played an important role in the development of China’s food industry.This paper aims to examine the effects of China’s grain science and technology policies on food security.It quantitatively assesses China’s food security by analyzing the main contents and development trends of China’s food science technology policies through the text metrology method,and then investigates the effects of grain science and technology policies on food security by employing a provincial dynamic panel model.The results show that food security in China is all-round developed,and that the release frequency and cumulative effect of grain science and technology policies play a significant role in promoting food security.Powerful grain science and technology policies can effectively guarantee China’s food security.

Dynamic change of agricultural energy efficiency and its influencing factors in China

In order to practice the concept of‘lucid waters and lush mountains are invaluable assets’and promote the green development of agriculture,it is necessary to improve the efficiency of agricultural energy utilization.Based on the panel data of 28 provinces from 1995 to 2018,this paper calculated China’s agricultural energy input from two categories of direct energy and indirect energy,and used EBM(Epsilon-based Measure)mixed distance function model to measure the energy efficiency of agriculture in China.The nuclear density function and spatial autocorrelation were used to analyze the dynamic evolution of agricultural energy efficiency,and the dynamic panel model was used to analyze the influencing factors of agricultural energy efficiency.The results showed that:①From 1995 to 2018,the total agricultural energy input had increased year by year in China,with an average annual growth rate of 2%.Energy input structure changed from indirect energy-based to direct energy-based.Agricultural energy efficiency showed an evolutionary trend of‘rising-stagnating-rising rapidly’in China.The agricultural energy efficiency was generally low in China,and there was a large space for improvement in agricultural energy efficiency.②From 1995 to 2018,the average annual growth rate of agricultural energy efficiency in the eastern,central and western regions was 2.7%,1.9%and 1.4%respectively.In 2018,the agricultural energy efficiency in the eastern,central and western regions was 0.81,0.71 and 0.59 respectively.The gap between regions was expanding rapidly,and the agricultural energy efficiency in the central and western regions needed to be improved.③From 1995 to 2018,the agricultural energy efficiency of each province was polarized and the absolute gap was widened.There was obvious improvement in agricultural energy efficiency in Guangdong,Shandong,Jiangxi,Jiangsu,Liaoning and Tianjin,while the agricultural energy efficiency of Xinjiang,Guizhou,Zhejiang,Shanghai,and Inner Mongolia deteriorated.④From 1995 to 2018,there was no global spatial correlation of China’s agricultural energy efficiency.However,local‘high-high’concentration gradually appeared in the eastern region since 2010.⑤The first lag of energy efficiency had a significant positive impact on agricultural energy efficiency,and agricultural energy efficiency improvement had a time lag.The level of human capital,per capita net income of farmers and the level of urbanizaton had a significant positive impact on agricultural energy efficiency.The disaster rate,the level of development of secondary and tertiary industries,and the level of opening up had a significant negative impact on agricultural energy efficiency.In the implementation of the strategy of rural revitalization,we should focus on the central and western regions,take the cultivation of professional farmers as the key,focus on improving agricultural production conditions,enhance the level of cooperation between regions,exert the leading role of the secondary and tertiary industries,and enhance the ability of agricultural disaster prevention and mitigation.

Agglomeration and Employment Density:Test Based on Panel Data of Prefecture-Level Cities of China

Related factors for measuring urban agglomeration effect were studied firstly.Then,panel data of 283 prefecture level cities of China were collected to analyze the effect of agglomeration on employment density.Besides,fixed effect model was applied to analyze static panel data,and two-step generalized method of moments(GMM) estimator was employed to analyze dynamic panel data.Results reveal that per capita regional GDP,public medical care level,and population mobility have significant effect on employment density.Therefore,there exists effect of agglomeration economy in prefecture level cities of China in the current stage.

AN IMPROVEMENT FOR LOWER－ORDER PANEL METHOD BASED ON THE DIRICHLET BOUNDARY CONDITION

An improved algorithm for velocity field of general configurations ispresentd for low-order panel method based on the internal Dirichlet boundary condi-tion. A direct calculating method for the velocity distribution by means of a limit pro-cess combining with analytic evaluation of higher-order singular integrals instead of theconventional method of doublet strength gradient is devised in order to avoid the diffi-culty of edge extrapolation of doublet strength. The problem of substantialunderpredictions of the induced drag coefficient obtained from the VSAERO analysisdisappears for the present improved algorithm. Illustrative calculations for several testcases such as swept back wing, swept forward wing and wing-body combination showthat the accuracy of results may be improved and is competitive with high-order panelmethod. In addition, the present direct integral method can be used to evaluate the ve-locity distribution for external flow field correctly, where the method of gradient cannot be used at all.

Spatial spillover effects of official development assistance on environmental pressure in sub-Saharan African(SSA)countries

Impoverished sub-Saharan Africa(SSA)is under increasing environmental pressure from global environmental changes.It is now generally accepted in academic circles that economic development in SSA countries can cause environmental pressure in other countries.However,there is research gap on the impact of economic assistance on environmental pressure in SSA countries and whether economic assistance causes spatial spillovers of environ-mental pressure between SSA countries.To better understand the impact of economic assistance on environmental pressures in SSA,a dynamic spatial Dubin panel model was developed.It helped us explore the spatial spillover effects of economic assistance on environmental pressures in recipient countries based on the panel data from 34 SSA countries.The results show that economic assistance had a positive stimulating effect on environmen-tal pressures of recipient countries,which means that the degree of human disturbance to the environment has deepened.Due to the regional correlation effect,neighboring countries were saddled with environmental pres-sures from the target country.Moreover,environmental pressures have time inertia,which can easily produce a snowball effect.The decomposition of effects shows that the impact of economic assistance on environmental pressures is relatively minor.Environmental pressures have spillover effects,so to deal with diffuse risks,joint regional prevention and control policies should be developed.

Effect of China’s technology spillovers on energy intensity in Africa

Empirical studies on the effects of China-African economic relations on energy intensity in Africa are scarce.To fill the gap in the literature,this study investigates the technology spillover effects of the China-Africa trade and investment relations on energy intensity.It uses both linear and nonlinear dynamic panel estimation methods for 42 African countries from 2003 to 2015.The results show that China's technology spillover through imports significantly reduces energy intensity in Africa.The findings are consistent across specifications and sample groups.Moreover,the technology spillover coming from foreign direct investment(FDI)improves energy intensity,particularly in lower-middle-income African countries.The dynamic threshold estimation results show that countries'absorptive ability is important for technology spillover effects of FDI and imports on energy intensity.The results suggest that countries'absorptive capacity should be increased to maximize the benefits of trade and investment technology spillovers.

Seismic earth pressures on flexible cantilever retaining walls with deformable inclusions

In this study, the results of 1-g shaking table tests performed on small-scale flexible cantilever wallmodels retaining composite backfill made of a deformable geofoam inclusion and granular cohesionlessmaterial were presented. Two different polystyrene materials were utilized as deformable inclusions.Lateral dynamic earth pressures and wall displacements at different elevations of the retaining wallmodel were monitored during the tests. The earth pressures and displacements of the retaining wallswith deformable inclusions were compared with those of the models without geofoam inclusions.Comparisons indicated that geofoam panels of low stiffness installed against the retaining wall modelaffect displacement and dynamic lateral pressure profile along the wall height. Depending on the inclusioncharacteristics and the wall flexibility, up to 50% reduction in dynamic earth pressures wasobserved. The efficiency of load and displacement reduction decreased as the flexibility ratio of the wallmodel increased. On the other hand, dynamic load reduction efficiency of the deformable inclusionincreased as the amplitude and frequency ratio of the seismic excitation increased. Relative flexibility ofthe deformable layer （the thickness and the elastic stiffness of the polystyrene material） played animportant role in the amount of load reduction. Dynamic earth pressure coefficients were compared withthose calculated with an analytical approach. Pressure coefficients calculated with this method werefound to be in good agreement with the results of the tests performed on the wall model having lowflexibility ratio. It was observed that deformable inclusions reduce residual wall stresses observed at theend of seismic excitation thus contributing to the post-earthquake stability of the retaining wall. Thegraphs presented within this paper regarding the dynamic earth pressure coefficients versus the wallflexibility and inclusion characteristics may serve for the seismic design of full-scale retaining walls withdeformable polystyrene inclusions. 2014 Institute of Rock and Soil Mechanics, Chinese Academy of Sciences. Production and hosting byElsevier B.V. All rights reserved.

Unveiling the impact and mechanism of digital technology on agricultural economic resilience

Enhancing the economic resilience of agriculture is essential for promoting sustainable and high-quality agricultural development.The emergence of digital technology has created new opportunities in this field.However,existing research predominantly focuses on traditional agricultural factors and technologies.Therefore,the impact of digital technology on agricultural economic resilience within the broader context of the“production-operation-industry”system in agriculture has not been comprehensively explored.To bridge this gap,this study analyzes panel data from 30 Chinese provinces from 2011 to 2020.It employs the static Van Dorn’s law and a dynamic spatial panel model to examine how digital technology empowers agricultural resilience.The findings indicate a continuous strengthening of digital technology development in China,albeit with significant polarization and spatial imbalances.Moreover,the resilience of the agricultural economy undergoes notable fluctuations,initially narrowing and subsequently displaying an upward trend.Digital technology clearly plays a pivotal role in empowering resilience through agricultural scale operation,industrial transformation,and technological progress.Its impact,particularly on the promotion of resilience in the eastern region and non-grain-producing areas and on high-level agricultural economies,also shows regional and technological variations.

Do Macroeconomic Determinants of Non-Performing Loans Vary with the Income Levels of Countries?

This paper explores the macroeconomic determinants of non-performing loans(NPL) in 19 Asian countries(low to high income economies) using the Generalized Method of Moments estimation approach based on the economic data for the period between 1998 and 2015. The categorization of the economies is based on the average gross national income per capita as set by the World Bank.Specifically, the paper aims to evaluate if the determinants of NPL vary with the income levels of the countries. The results indicate that the NPL is strongly influenced by the inflation rate. The effect is,however, negative in the high-income and the middle-income countries and positive in the low-income countries. The GDP per capita has a dynamic negative relationship with the NPL in the high-income and the low-income countries. The remittance has a significant positive association in the high-income and a significant negative association in the low-income countries. Similarly, the unemployment rate has a positive effect on NPL in the middle-income and the low-income countries. With the rise in the official exchange rate, the NPL level increases in the low-income countries. The overall estimation results suggest that the NPL in Asian banking system depend on some key macroeconomic variables,such as unemployment rate, inflation rate, official exchange rate, remittance received and gross domestic product per capita, and these associations vary with the income level of the countries. Therefore,economic level of a country should be carefully considered while formulating credit policy to minimize credit risks in the banking system.

Estimating the effect of minimum wage on firm profitability in China

Using the firm-level panel datasets and hand-collected data on county level minimum wage,this paper estimates the effect of minimum wage on firm profitability.As firms may take time to adjust in response to changes in minimum wage,this paper estimates a dynamic panel model with lagged minimum wage.To capture the heterogeneous effect of minimum wage on profitability,this paper further estimates quantile regression dynamic panel model.The estimation results suggest that the effect on firm profitability of minimum wage in the current year is negative across the whole conditional distribution of profitability and it exhibits an inverted-U shape across conditional quantiles.The effect on profitability of lagged minimum wage is positive at the 5th,10th,15th quantiles,negative at the 90th and 95th quantiles,and not significant at other quantiles.Turning to the overall effect on profitability of minimum wage,we find that minimum wage exerts significantly negative effect on profitability at the 5th quantile and quantiles higher than 40th and the absolute value of the effect of minimum wage increases with these quantiles.For other quantiles,the overall effect of minimum wage on profitability is negligible.

The effects of financial liberalization on productivity:Evidence from India’s manufacturing sector

Using a panel of India’s registered manufacturing firms and both economy-wide and firm-level financial data,we investigate the effects of India’s financial liberalization on the productivity of its manufacturing sector in the 1990s and 2000s.Our dynamic panel analysis shows that the series of financial liberalization policies/measures,at both the macro and micro levels,significantly enhanced the productivity of the manufacturing sector.Total factor productivity increased for all firms,including those owned by the state government,with greater gains for the firms in the private and foreign sectors.Our results suggest that policies favoring financial liberalization should be pursued further in order for India to foster higher economic growth.