This paper takes 23 features of China's actively managed funds from 2015 to 2024 as samples, and predicts the future returns of the funds based on traditional linear regression models, Elastic Net models, Decision Tree models, Random Forest models, Ridge Regression models and Lasso Regression models, and constructs investment portfolios in groups according to the predicted return. The effectiveness of the investment portfolio construction is examined by analyzing the Sharpe ratio, information ratio, volatility and maximum drawdown rate of real data, and the predictive ability and stability of the features are examined by analyzing the value of Rank IC and ICIR of the features. The study found that the features used in this paper can provide rich information for the model, and most of the features have strong predictive ability and predictive stability; the performance of each investment portfolio is consistent with the real data; compared with the traditional linear model, the machine learning method has higher prediction accuracy, more flexibility and stability.

China's economic and social growth is significantly impacted by how to support the high-quality development of businesses. Using A-share listed companies in Shanghai and Shenzhen from 2007 to 2022 as the research object, this paper tests the intermediary mechanisms of financing constraints, information asymmetry, and government subsidies, as well as the heterogeneous characteristics of whether the enterprises are state-owned or not, whether they are high-tech or not, and the regionality of the enterprises. It also empirically analyzes the impact of digital transformation on the high-quality development of enterprises. The research concludes that: digitalization can promote the high-quality development of enterprises by reducing financing constraints, increasing government subsidies, and increasing information asymmetry; and the promotional effect of the digital transformation on the high-quality development of enterprises is more significant in the eastern enterprises and state-owned enterprises. The study finds that the digital transformation of enterprises can significantly promote the high-quality development of enterprises, and the conclusion still holds after a series of robustness and endogeneity tests. The results add to the body of knowledge on enterprise high-quality development and digital transformation research. They also offer theoretical pointers for furthering the growth of enterprise high-quality initiatives.

For a long time, the impact of environmental factors on stock returns has always been a hot topic. An unfavorable environment for investors affects investors' emotions and causes them to have negative emotions, which leads to changes in investors' purchase preferences and thus affects stock returns. This paper uses the daily stock return data of the daily return rate of all outstanding A- shares on the Shanghai Stock Exchange in China in 2014, the local daily AQI data of 363 cities in 2014, and other control variable data to explore the effect of air quality on stock return through panel regression. The reasons for the effect of air quality on stock returns will be explained in this paper from the perspective of investor emotions. The results show that the worse the air quality is, the lower the stock return will be. This result still holds when controlling for city fixed effects and month fixed effects. Moreover, the interference of other control variables such as circulation market value and market risk premium on the results is excluded, indicating that investors' sentiment does affect stock returns.

The Internet economy and rural e-commerce are undergoing significant transformation, and in this regard, researching how it encourages rural residents to upgrade their consumption has great practical implications for promoting rural rejuvenation and removing the economic cycle's obstruction. Panel data from 31 provinces are gathered for this article between 2011 and 2021. It uses a time-fixed effects model to investigate the connection between rural inhabitants' upgraded consumption and the growth of rural e-commerce. Through three mechanisms—stimulating residents' consumption demand, raising residents' per capita income, and improving the quality of life—rural e-commerce is found to have a considerable beneficial effect on rural residents' consumption upgrading and passes a number of robustness tests. Rural e-commerce development promotes residents' consumption upgrading in the western region most significantly. Rural e-commerce is maintaining a strong development momentum, promoting residents' consumption upgrading, economic transformation, and social change.

The impact and mechanism of the business environment on the digital transformation of enterprises are empirically studied in this paper, which uses data from Chinese A-share listed companies from 2017 to 2021 as a sample. Based on the regional business environment score, a time-fixed effect model is constructed to examine the influence of the business environment on the digital transformation of enterprises. The empirical findings demonstrate that a favorable business environment has a substantial impact on the digital transformation of businesses. The mechanism of action for this effect is that business environment reform raises the bar for urban marketization, improves infrastructure, and fosters enterprise innovation. Subsequent analyses of heterogeneity revealed that the business environment had a greater impact on the digital transformation of enterprises in central and western areas, as well as in locations with larger levels of government participation and SOEs. The results can offer valuable perspectives for advancing the digital transformation of businesses and strengthening the reform of the business environment.

Within the ongoing context of social informatization, China has achieved considerable development in its digital government construction. However, there remains a lack of systematic and scientific policy review concerning China’s digital government construction. This paper investigates 290 policies pertinent to China’s digitalization efforts from November 1995 to July 2024. By utilizing methods including word frequency analysis, semantic network analysis, and topic clustering, it conducts a systematic examination of the policy transitions and developmental framework of China’s digital government from 1995 to 2024. The trajectory of China’s digital government construction policies has encompassed three distinct phases: the initialization of government informatization and e-governance, the era of the Internet Plus Government Services initiative, and the current phase of digital government construction. These policies have been modified in response to the changing priorities of government digitalization, exhibiting both continuity and adaptability, and are in synergy with the progressive establishment of a service-oriented government in China.

Amidst the escalating global climate crisis and mounting environmental protection consciousness, digital transformation and green innovation have emerged as pivotal strategies for enterprises to pursue sustainable development. Both businesses and governments are increasingly recognizing the importance of environmental stewardship, not only by enacting policies at the governmental level but also by integrating green principles into their operational practices. Simultaneously, through embracing digital transformation, companies are not only enhancing operational efficiency but also achieving resource optimization and recycling, thereby fueling sustainable growth. This highlights the synergy between technology and environmental protection as a key driver of healthy and green socio-economic development worldwide.Digital transformation is catalyzing green innovation through the integration of advanced digital technologies, not only by injecting new vitality into the process but also by optimizing internal business processes, significantly boosting operational efficiency, and strengthening green supply chain management mechanisms. This comprehensive approach enables companies to achieve higher environmental performance goals.This study meticulously analyzes empirical data from Chinese A-share listed companies, elucidating how digital transformation and green innovation specifically contribute to environmental performance improvement. It further validates the mediating role of green innovation as a crucial mechanism linking digital transformation to enhanced environmental performance.The findings reveal that the digital transformation of enterprises significantly boosts their environmental performance, positively impacting their sustainable development by accelerating the pace of green innovation. This study enriches the theoretical framework in the domain of digital transformation and green innovation, offering a novel perspective through empirical analysis, thus propelling the advancement of theory in this field.

Aircraft contrails significantly impact the environment, primarily because they emit gases such as carbon dioxide and nitrogen oxides. These contrails are a type of 'cirrus cloud,' composed of young linear condensation trails and older, irregularly shaped trails that they produce. As contrails form, the byproducts of fuel combustion, such as carbon dioxide, linger in the air for a long time, altering the concentration of carbon dioxide in the atmosphere and causing the atmospheric temperature to rise. Different fuels produce different gases when burned, some of which may be harmful to the environment. In this article, this paper will summarize articles on how different fuels affect contrails and the environment. The results show that different fuels produce different gases when burned, some of which are harmful to the environment, while others are not. Traditional fuels like jet fuel generate carbon dioxide and water vapor, whereas new energy sources like hydrogen do not produce carbon dioxide. Different fuel types primarily influence aircraft contrails through their combustion products and efficiency. Aviation kerosene, as the mainstream fuel, produces water vapor that easily forms contrails under high-altitude, low-temperature conditions. In contrast, biofuels or alternative fuels, due to differences in their chemical composition, may produce less water vapor or other gases that affect contrail formation during combustion.

In recent years, the excessive use of fossil fuels has led to global warming and a series of environmental crises. Carbon emissions trading, as a market-based mechanism to reduce carbon emissions, has received widespread attention and application. This paper investigates the dynamic dependency and causal interrelationships between Chinese pilot city carbon markets and the European Union Emissions Trading System (EU ETS). Using the wavelet analysis method, this paper empirically examines the data of various cities' carbon markets in China and the EU ETS from June 2014 to February 2023. Significant differences are found in the relationships between Chinese city carbon markets and the EU ETS. The study indicates that, with the exception of Shenzhen, the dynamic interactions between Chinese city carbon markets are weak in the short term but gradually strengthen in the long term. Not all city carbon markets in China have strong correlations, but they are closely related to factors such as local policies, economies, and industrial structures. There is no stable lead-lag relationship among the prices of carbon markets in different Chinese cities. After 2022, there is a trend of positive lag relationship of carbon market prices in Chinese cities (such as Guangdong, Shanghai, Chongqing) with those in the EU ETS. This paper summarizes the relationship between Chinese city carbon markets and the EU ETS and puts forward suggestions for the development of Chinese carbon market construction, including improving institutional systems, strengthening market supervision, promoting technological innovation, and implementing policies to stabilize price fluctuations.

With the emergence of the "wave of returning to China" and the continuous introduction of a series of talent introduction policies by the country, talents with overseas backgrounds have begun to hold key positions in the top management of enterprises, and their impact on the development of Chinese enterprises has received widespread attention.This article selects A-share listed companies in Shanghai and Shenzhen from 2007 to 2021 as samples to empirically examine the impact of overseas backgrounds of executives on digital transformation of enterprises. Research has found that executives with overseas backgrounds can promote digital transformation in enterprises. Mechanism testing found that executives with overseas backgrounds promote digital transformation of enterprises by enhancing their innovation capabilities and reducing agency costs. Expanded research has found that the promoting effect of overseas executives on digital transformation of enterprises is more pronounced in state-owned, low information asymmetry, and small and medium-sized enterprises.The conclusion of this article not only enriches the influencing factors on the driving force of enterprise digital transformation, but also provides valuable evidence for enterprises on how to accurately position and attract management elites, as well as plan future development.