Impacts of high-speed rail on urban smog pollution in China: A spatial difference-in-difference approach

Estimating the effectiveness of marked sidewalks: An application of the spatial causality approach

Various safety enhancements and policies have been proposed to enhance pedestrian safety and minimize vehicle-pedestrian accidents. A relatively recent approach involves marked sidewalks delineated by painted pathways, particularly in Asia's crowded urban centers, offering a cost-effective and space-efficient alternative to traditional paved sidewalks. While this measure has garnered interest, few studies have rigorously evaluated its effectiveness. Current before-after studies often use correlation-based approaches like regression, lacking effective consideration of causal relationships and confounding variables. Moreover, spatial heterogeneity in crash data is frequently overlooked during causal inference analyses, potentially leading to inaccurate estimations. This study introduces a geographically weighted difference-in-difference (GWDID) method to address these gaps and estimate the safety impact of marked sidewalks. This approach considers spatial heterogeneity within the dataset in the spatial causal inference framework, providing a more nuanced understanding of the intervention's effects. The simplicity of the modeling process makes it applicable to various study designs relying solely on pre- and post-exposure outcome measurements. Conventional DIDs and Spatial Lag-DID models were used for comparison. The dataset we utilized included a total of 13,641 pedestrian crashes across Taipei City, Taiwan. Then the crash point data was transformed into continuous probability values to determine the crash risk on each road segment using network kernel density estimation (NKDE). The treatment group comprised 1,407 road segments with marked sidewalks, while the control group comprised 3,097 segments with similar road widths. The pre-development program period was in 2017, and the post-development period was in 2020. Results showed that the GWDID model outperformed the spatial lag DID and traditional DID models. As a local causality model, it illustrated spatial heterogeneity in installing marked sidewalks. The program significantly reduced pedestrian crash risk in 43% of the total road segments in the treatment group. The coefficient distribution map revealed a range from -22.327 to 2.600, with over 95% of the area yielding negative values, indicating reduced crash risk after installing marked sidewalks. Notably, the impact of crash risk reduction increased from rural to urban areas, emphasizing the importance of considering spatial heterogeneity in transportation safety policy assessments.

Does digital infrastructure construction impact urban carbon emission reduction? Evidence from China's smart city construction

As the cornerstone of the digital economy, the construction of digital infrastructure plays a crucial role in promoting China's high-quality economic growth.. Against the backdrop of the "dual-carbon" goals, the development of digital infrastructure will provide new momentum for carbon emissions reduction in urban areas. This study utilizes unbalanced panel data from 277 prefecture-level cities in China between 2008 and 2019, treating the smart city construction as a quasi-natural experiment, to systematically evaluate the impact of the pilot construction of smart city on urban carbon emissions intensity. The research findings reveal that the construction of the smart city has significantly contributed to the reduction of urban carbon emissions intensity, indicating that digital infrastructure contributes to urban carbon emission reduction. The reduction of carbon emissions resulting from smart city construction is particularly significant in the East and Central regions., as well as regions with high financial development levels, regions with high human capital levels and non resource-based cities. The construction of the smart city primarily achieves the reduction of urban carbon emissions intensity through two main pathways: improving the penetration rate of digital infrastructure and enhancing technological innovation capability. Therefore, this study recommends that local governments strengthen the integration and penetration of digital infrastructure with traditional industries, foster urban innovation vitality, and accelerate the transformation towards green and low-carbon cities.

Can the construction of a high-speed rail alleviate haze pollution: an empirical analysis based on social networks and dynamic spatial econometric models

With the increase in haze pollution in Chinese cities, answering the question of whether using a high-speed rail (HSR) as a green and efficient transportation system can alleviate haze pollution in China has become a research hotspot. This study empirically tests the impact of HSR network construction on haze pollution and its spatial spillover effects. (1) The construction of a HSR would have a mitigation effect on haze pollution in node cities and surrounding cities, and the more developed the HSR is, the more significant that this effect would be. (2) Haze pollution persists for a long time, the haze pollution from the previous year may have a positive promoting effect on the haze pollution in the following year. (3) The use of a HSR reduces haze pollution by replacing traditional road transportation and promoting industrial structure upgrading and technological innovation. (4) The inhibitory effect of HSR use on haze pollution varies due to regional differences and variation in city size.

How does the location of high-speed railway stations affect the emission reduction effect of industrial structure upgrading?

The opening of high-speed railway (HSR) has accelerated the reorganization and reallocation of regional production elements, and constantly promoted the adjustment and upgrading of industrial structure. The cleaner production effect produced by industrial structure upgrading is of great significance to industrial pollution reduction. As a bridge connecting resources within the city and elements outside the city, the location of HSR stations has become an important factor affecting the structural emission reduction effect. Based on the data of 285 prefecture level and above cities in China from 2004 to 2018, this paper investigates the structural emission reduction effects of HSR opening and the impact of HSR station location on it by employing difference-in-differences (DID) model combined with mediation effect method. The results demonstrate that the opening of HSR has significant structural emission reduction effect, and the upgrading of inter-industry structure and the intra-industry structure are important mechanisms for HSR to achieve industrial emission reduction. The structural emission reduction effect of HSR opening is closely related to the location of HSR stations. With the increase of the distance between HSR station and city center, the industrial structure upgrading effect will continue to weaken, thus inhibiting the exertion of structural emission reduction effect, of which 10 km away from the city center is the optimal site strategy for the HSR service to give full play to the structural emission reduction effect, and exceeding 50 km will be significantly detrimental to its role in promoting industrial structure upgrading.

Public acceptance of residential photovoltaic installation: A case study in China

Residential photovoltaics (PV) presents an effective means of achieving low-carbon development, owing to its installation flexibility and resource-saving properties. To explore the residents' behavioral intentions to purchase and install residential PV systems, this study collected 1424 samples and analyze the impact of different policies on residents' adoption of residential PV using the theory of TPB and the Partial Least Squares Structural Equation Model (PLS-SEM). The main conclusions are summarized as follows: (1) Bungalow residents exhibit a stronger inclination to install residential PV than building residents. (2) Perceived reward (PR) affects installation intention (II) more than perceived guide (PG) among bungalow residents. (3) Both PR and PG indirectly affect II through Perceived behavioral control (PBC) among bungalow residents. Economic policies, represented by PR, are likely to have more substantial indirect effects than propaganda and guidance policies. The findings suggest that China's recent residential PV installation policies should increase users' trust and guide the future decline of subsidy policy.

Transportation infrastructure and eco-environmental quality: Evidence from China's high-speed rail

Ecological civilization construction is China's national development strategy, and improving the urban eco-environmental quality is the key to accelerating this strategy, while the high-speed rail (HSR) opening is an important factor affecting the urban eco-environmental quality. Using panel data of 290 cities in China from 2004 to 2020, this study explores the impact of HSR opening on urban eco-environmental quality and its heterogeneity from the perspective of direct impact and interaction between HSR connected cities. Compared with cities without HSR service, the eco-environmental quality of cities with HSR service has significantly increased by 0.023 standard deviations, which is about 4.11% of the total change in urban eco-environmental quality in the same period. Second, there is an inverted U-shaped relationship between eco-environmental quality and urban space expansion. Third, the impact of HSR on eco-environmental quality is heterogeneous, mainly manifested in different cities and urban agglomerations. It means that the government should focus on the differences in the economic foundation and development characteristics of various regions, steadily push forward the construction and operation of the HSR, and speed up the renovation of existing lines to help the green development of cities. The research results provide a policy basis for the government to handle the relationship between infrastructure construction and eco-environmental quality, and effectively promote green sustainable development.

How does the opening of China's high-speed rail affect the spatial mismatch of haze pollution and economic growth?

A better reconciliation of haze pollution and economic growth has become the social consensus in China. The development of China's economy and air quality will be significantly impacted by its efforts to create high-speed rail (HSR). Based on panel data from 265 prefecture-level cities in China from 2003 to 2019, this paper investigates how the opening of HSR affects the spatial mismatch of haze pollution and economic growth by using the spatial mismatch index model, multi-period difference-in-differences (DID) model, and intermediary effect model. We find that the spatial mismatch in China has an overall decreasing trend. And its spatial agglomeration is dominated by low levels. Further empirical analysis shows that HSR opening can effectively restrain the spatial mismatch. Even after some robustness tests and endogenous treatment, the conclusion is still valid. In addition, population density, FDI, and industrial structure are also explicit factors affecting the spatial mismatch. Second, there is significant heterogeneity in the impact. This is reflected in the fact that HSR opening can suppress the spatial mismatch of service-oriented cities and the eastern region, while other cities and regions have no noticeable effect. Third, spatial transfer of haze pollution (STHP) and balanced development of economic growth (BEG) are two important conduction paths for the opening of HSR to affect the spatial mismatch. Specifically, HSR opening can constrain the spatial mismatch by inhibiting STHP and BEG. Based on the above findings, recommendations related to promoting a better harmony between haze pollution and economic growth are proposed.

Operation of high-speed rail and reduction of corporate pollution: evidence from China

As an environmentally friendly means of transport, the high-speed rail (HSR) is conducive to promoting corporate performance. An innovative approach extends the impact of HSR networks on pollution emissions from the regional level to the micro-enterprise level. Based on the quasi-natural experiment of the opening of HSR, a difference-in-difference model is used to investigate the impact of HSR on enterprise pollution emission levels and its action mechanism by using the matched data from the Chinese Enterprise Pollution Emission Database, the Chinese Industrial Enterprise Database, and the Chinese City Statistical Yearbook from 2000 to 2010. The results show that opening HSR significantly reduces the enterprises' pollution emission level, while reducing the number of polluting enterprises and transportation costs as well as improving the innovation capacity of enterprises are the corresponding action mechanisms. The impact of HSR on the enterprises' pollution emission varies with industry intensity, population size, and regional economic development level. The conclusions not only provide important insights to increase the ecological quality of China's environment through transportation infrastructure upgrades but also bring some guidance to more developing countries to improve their air environment.

The Impact of SO2 Emissions Trading Scheme on Firm's Environmental Performance: A Channel from Robot Application

Improving the environmental performance of enterprises is the key to achieving the goal of energy conservation, emission reduction and green development. This paper investigates the causal impact on the firm's environmental performance of China's SO₂ emissions trading scheme (SO₂ ETS), a market-based environmental regulation. Different from the verification mechanism of the Porter hypothesis in the existing literature, we examine the micro mechanism of both emission reduction and efficiency gains of enterprises from the perspective of robot application based on Chinese firm-level data from 2000 to 2013. The paper found that SO₂ ETS significantly reduces the emission intensity of Chinese enterprises, and the results are still significant after a series of robustness tests and using instrumental variables to overcome the endogeneity problem. Mechanism analysis shows that the reduction of pollutant emissions and the productivity effect of robot application are two significant channels for SO₂ ETS to improve the firm's environmental performance. In addition, in resource-based and recession-oriented cities, the SO₂ ETS has a more significant effect on enterprise emission reduction. These findings provide empirical evidence and policy enlightenment for enterprises to promote market-oriented environmental regulation and release institutional dividends in the process of industrial automation transformation, green and sustainable development.

Examining the Impact of Regional Development Policy on Industrial Structure Upgrading: Quasi-Experimental Evidence from China

"Guiding Opinions on Relying on the Golden Waterway to Promote the Development of the Yangtze River Economic Belt (YREB)", the "YREB Development Policy", is a national Chinese policy aiming to promote industrial structure upgrading and high-quality development in the YREB. To test the effects of this policy, we used 2009-2019 data from 283 cities to examine whether its implementation promoted regional industrial structure upgrading. The YREB Development Policy positively impacted industrial structure advancement but scarcely benefited industrial structure rationalization. Moreover, the impacts indicated a temporary, unsustainable influence on industrial structure advancement, presenting a clear U-shaped development trend. The YREB Development Policy can more significantly improve industrial structure upgrading in cities with large populations. The effects of this policy on industrial structure upgrading in the middle and lower reaches of the YREB are almost five times that in the upper reaches. In addition, the policy more greatly impacts the tertiary industry than the primary and secondary industries, especially in the lower reaches. These findings have policy-making implications, enrich the research regarding the YREB Development Policy impacts on industrial structure upgrading, and provide an empirical reference to improve subsequent policies.

Impact of High-Speed Rail Construction on the Environmental Sustainability of China’s Three Major Urban Agglomerations

Under the background of global warming, it is of great significance to explore how to realize environmentally sustainable development. This paper takes China’s three major urban agglomerations as the research objects: Yangtze River Delta, Beijing–Tianjin–Hebei, and Pearl River Delta. Generally, we use carbon emission efficiency to represent the sustainable development of the environment. Then we use the city-level panel data of the three urban agglomerations from 2006 to 2019 to construct the slacks-based measure integrating data envelopment (SBM-DEA) model for calculating each city’s carbon dioxide emission efficiency. Finally, we construct the spatial difference-in-differences (SDID) model to explore the impact of high-speed rail construction on each urban agglomeration’s carbon dioxide emission efficiency and its internal mechanism. The findings are as follows: (1) On the whole, high-speed rail construction improves urban agglomerations’ carbon dioxide emission efficiency. Meanwhile, it has a positive spatial spillover effect on surrounding areas. (2) In terms of urban agglomerations, high-speed rail construction has significantly promoted carbon emission efficiency in the Beijing–Tianjin–Hebei region. However, it has had negative external effects on the surrounding areas. (3) From the perspective of mechanism analysis, the construction of high-speed rail has promoted manufacturing agglomeration in the Pearl River Delta region and, at the same time, has had a negative impact on the local carbon dioxide emission efficiency. This study has strong policy implications for promoting the sustainable development of the three major urban agglomerations.