3.1. Sample Selection and Data Sources
This empirical study focuses on Chinese publicly listed manufacturing companies from 2011 to 2020. We selected these companies as our sample for two reasons. Firstly, China, one of the biggest developing countries in the world, has a diverse industrial structure that includes manufacturing, services, and high-tech sectors, providing a wide range of samples for in-depth exploration of the relationship between digital technology adoption and green human resource allocation. Secondly, the Chinese government actively promotes green sustainable development and digital transformation, introducing a series of specific policies and targets that impose higher requirements on listed manufacturing companies. This unique policy environment and practical foundation make China an ideal setting for this research. Moreover, Chinese publicly listed manufacturing companies have enormous market share and international influence, making their experiences and development paths beneficial for other countries and regions in advancing sustainable development goals. Therefore, selecting Chinese publicly listed manufacturing companies for empirical research is reasonable and contributes to a profound understanding and practical application.
Chinese publicly listed manufacturing companies and their financial data are obtained from the Wind database. Wind is a leading financial data service provider that delivers comprehensive financial market data to users, covering various asset classes such as stocks, bonds, futures, and funds. The database provides real-time market data and includes rich historical data, enabling users to conduct comprehensive market analyses and reviews. In addition, Wind offers financial statement data for listed companies, supporting users in conducting company financial analysis. With powerful data analysis tools, users can engage in sophisticated market research and quantitative analysis. Moreover, Wind provides macroeconomic indicators and industry data, offering economic information at the macro level. Through professional services and diverse data offerings, Wind provides reliable decision support for investment institutions and financial practitioners, empowering them to make informed investment strategies.
Corporate social responsibility (CSR) data were taken from Hexun.com. Hexun.com, as one of China’s leading financial information service providers, is committed to delivering comprehensive and timely financial information, market data, and analytical reports to a broad audience of investors and professionals. The content on Hexun.com covers various financial markets, including stocks, funds, bonds, foreign exchange, macroeconomic indicators, industry dynamics, and financial commentary. The website offers real-time market quotes, financial news, insights from professional analysts, and an interactive user community, providing users with a comprehensive financial information platform. Notably, Hexun.com has gained recognition for releasing comprehensive social responsibility scores for Chinese-listed companies, serving as a metric for evaluating corporate social responsibility performance. We utilized Python software to extract annual social responsibility data from Hexun.com for each listed company. The patent data were collected from the Chinese National Intellectual Property Administration and the Himmpat database.
The steps used were as follows: Firstly, in the stock module of the Wind Database, choose the “Multidimensional Data for Stocks” option. Select all listed companies in the “Market Type” option within the available range. Choose indicators such as enterprise type to identify the Chinese-listed manufacturing companies. Next, within the database indicators, select data for enterprise finance, enterprise age, enterprise size, ownership nature, pollution attributes, debt-to-equity ratio, enterprise growth, and industry classification, exporting them to Excel. Subsequently, perform calculations on the exported Excel data based on different indicator formulas and transform them into panel data.
Secondly, based on the list of specific names of Chinese manufacturing companies obtained from the Wind database, we retrieved patent data for each company from the Himmpat patent database. Due to the Chinese patent regulations stipulating an 18-month delay in the publication of invention patents, we collected data up to 2020 to ensure accuracy. Specifically, we constructed a patent retrieval formula, “Applicant = Company Name, Patent Application Time from 2011 to 2020,” to retrieve specific patent data for each listed company. We captured each patent’s application number, publication number, title, applicant, inventor, application date, IPC classification code, CPC classification code, and citation information. Subsequently, we split the applicant field in the obtained patent dataset. We precisely matched the list of Chinese manufacturing companies and their stock codes to eliminate data where “the original applicant and patentee are non-target companies, but the current patentee is the target company”. Each patent was assigned a unique stock code to ease subsequent data integration. The preprocessed dataset accumulated over 860,000 entries.
Thirdly, we utilized tools such as Python to conduct a detailed analysis of the green patent information for each listed company, including the number of inventors and patent applications related to green technologies. We employed the widely used CPC patent classification system to identify green patents based on categories Y02 and Y04. Specifically, leveraging a dataset of 860,000 patents, we utilized Python to extract data from the CPC column that included Y02 or Y04, facilitating the quantification of green patents. Subsequently, we split and consolidated inventor information from the extracted green patents to precisely calculate each company’s annual count of green inventors. This process not only aids in understanding a company’s performance in green innovation, but also establishes a reliable foundation for subsequent data analysis.
Fourthly, we extracted the patent numbers cited by each application and obtained more than 900,000 cited patent numbers. We then searched the database for these cited patents, extracting IPC classification codes, application numbers, and application years for each. This information is used to measure the dimensions of digital technology applications in subsequent analysis. For the definition of digital technology, this paper processes data according to the definition in the “Reference Relationship Table of the Core Industry Classification of the Digital Economy and the International Patent Classification (2023)” issued by China National Intellectual Property Administration [
67,
68]. We follow the degree centrality measurement mentioned in existing work [
69] to calculate network centrality metrics in structure and relational embeddings. According to a previous study, inter-firm cooperation ties often persist for 3–5 years [
70]. Therefore, the innovation network of listed enterprises involved in digital technology innovation during 2011–2020 is divided into ten periods in this study using a 3-year rolling time window. Specifically, when calculating the relationship embedding indicators and structural embedding of the innovation network using Python, we leveraged the powerful NetworkX network analysis library. Firstly, through NetworkX, we flexibly and efficiently constructed the digital technology innovation network, mapping each company as a node and representing their collaborative relationships with edges. The relationship embedding in this innovation network goes beyond a simple reflection of connections between companies; it is further refined to quantify the number of collaboration partners, providing in-depth insights into the collaborative network features of digital technology innovation. Regarding structural embedding, we relied on the rich algorithms offered by the NetworkX library in Python, particularly centrality metrics such as degree centrality. Degree centrality not only measures the level of connectivity for each company within the digital technology innovation network, but also reveals their importance and influence in the network structure by examining the number of adjacent nodes. This form of structural embedding not only offers a clear understanding of the position of each company within the innovation network, but also provides robust support for understanding their roles and contributions in collaborative relationships.
Finally, we used Python to merge the obtained and calculated patent indicators with enterprise financial and other indicators based on the consistency of stock listing codes and years. Unmatched companies with stock codes and companies that did not apply for patents during the observation period were excluded. After that, we obtained a sample of 1760 companies.
3.2. Variable Explanations
- (1)
Independent Variable—Digital Technology Application
Drawing on Blichfeldt (2021) [
38], this study divided digital technology applications into breadth and depth. Specifically, the digital technology application breadth (DTAB) measures the variety of digital technologies a company employs in its GTI processes. This metric measures how widely a corporation uses different digital technologies, such as the Internet of Things (IoT), artificial intelligence, blockchain, big data analytics, and virtual reality, to advance the development of green technologies. A higher DTAB indicates that a company extensively utilizes diverse digital technology to drive environmental innovation.
The digital technology application depth (DTAD) focuses on the proportion of specific digital technologies a company applies in GTI. This dimension highlights the critical role of digital technology in a company’s GTI. A high DTAD means that digital technology plays a significant and influential role in a company’s GTI, contributing substantially to innovation.
- (2)
Dependent Variable—GTI Performance
A company’s innovation achievements in environmental protection and sustainable development are primarily manifested through the invention of green-related new technologies, products, or methods that are granted unique invention patents. Green invention patents represent a company’s outstanding contributions to environmentally friendly innovations, signifying the company’s active commitment to goals such as resource efficiency, pollution reduction, and energy conservation [
71]. Following Liang (2022) [
72], this study measures a company’s performance in green innovation using the natural logarithm of the number of green invention patent applications submitted by the company. This objective metric verifies the company’s influence and innovation level in environmental innovation. A higher number of green invention patents indicates that the company has achieved significant results in GTI, providing a competitive advantage and contributing to the industry’s overall sustainability.
- (3)
Mediating Variable—Green Human Resource
Green human resources are a crucial component of green resource management, reflecting employees’ expertise and capabilities in green knowledge, skills, technological innovation, and environmental management [
73]. To measure the level of green human resources, this study adopts a measurement method based on the quantity of green technology research and development personnel, similar to Li et al. (2019) [
74]. Specifically, we rely on enterprise patent data from the Himmpat database to calculate the number of inventors involved in green technology inventions subject to patent applications each year and take the natural logarithm of this number. This measurement method accurately reflects the company’s green human resource allocation level. It enhances the comparability and interpretability of the research results, improving understanding of the dynamic interaction between applications of digital technology and green innovation.
- (4)
Moderating Variable—Digital Technology Innovation Network Embedding
This study comprehensively measures the DTIN embedding of enterprises, focusing primarily on two key dimensions: DTIN relationship embedding (NR) and DTIN structure embedding (NS).
NR focuses on the interactive relationships among enterprises within the DTIN. This dimension primarily assesses the degree of trust and reciprocity among enterprises, often measured by the strength of relationships. Strong connections between network members indicate more potential for information sharing and teamwork, essential for information searching, knowledge sharing, and collaborative development. In this study, we adopt the “number of collaborations between the target enterprise and its partners in the network” to measure DTIN relationship embedding [
69]. Specifically, we take the natural logarithm of the number of collaborations between the target enterprise and its partners in the network plus one as the measurement indicator, reflecting the strength of the enterprise’s relationships within the DTIN.
Alternatively, NS focuses on the impact of a company’s relative position within the DTIN. This study employs the degree centrality index to measure this dimension, indicating a company’s connectivity within the network [
75]. The higher a company’s degree of centrality, the more central it is within the network. The formula for calculating degree centrality is C(ni) = d(ni)/(n − 1), where n represents the total number of nodes, and d(ni) represents the number of times node ni is connected to other nodes. This index reflects the structural embedding of enterprises within the DTIN, which is their relative importance within the network. By measuring these two key dimensions, this study can comprehensively understand the degree of embedding of enterprises within the DTIN, including their interactive relationships with partners and their position within the network structure. This aids in a deeper exploration of the relationship between digital technology applications (including breadth and depth) and green human resource allocation, and investigates its impact on green innovation performance.
- (5)
Control Variables
Drawing from existing research, this paper primarily controls for the following variables. Firm age: The natural logarithm of the years from the establishment year to the observation year. Firm size: The natural logarithm of the company’s total assets. Ownership nature: Assign a value of 1 if the company is state-owned; otherwise, assign a value of 0. Pollution attribute: Takes the value 1 for heavily polluting companies and 0 otherwise. Financial leverage means the asset–liability ratio, calculated as the total liabilities divided by total assets. Firm growth: Calculated as the operating income difference between the current and prior periods divided by the prior period’s operating income. Corporate social responsibility: The natural logarithm of the corporate social responsibility score obtained from Hexun.com (
Table 1).
3.3. Model Design
The design draws upon data obtained from Chinese-listed manufacturing companies from 2011 to 2020. This study employs an ordinary least squares (OLS) mixed-effects model to scrutinize the connections among digital technology applications, green human resource allocation, enterprise DTIN embedding, and green innovation performance. Specifically, we designate digital technology application as the independent variable, GTI performance as the dependent variable, green human resource as the mediator variable, and enterprise DTIN embedding as the moderating variable. The ensuing empirical model is constructed as follows.
Firstly, we propose the following model to analyze how digital technology applications affect green innovation performance, corresponding to hypotheses H1a and H1b:
GIN is the dependent variable representing a company’s green innovation performance. DTA is the independent variable representing digital technology applications, including the DTABD. Controls refer to the control variables, including firm age, firm size, ownership nature, pollution attribute, asset-liability ratio, firm growth, industry affiliation, and corporate social responsibility. “i” and “t” respectively represent companies and years, and i,t denotes the residual terms.
Secondly, when investigating the mediating effect of a company’s green human resource allocation, as hypothesized in H2a and H2b, this study employs a three-step method to test the effect of green human resource allocation. The specific model is as follows:
GH is the mediating variable of green human resource allocation; other variables are mentioned above.
Third, we propose Model (5) to examine the moderating effect of enterprise DTIN embedding on the relationship between digital technology applications and green human resource allocation, as hypothesized in H3a and H3b:
N is the moderating variable of DTIN embedding, including the relational and structural embedding of the DTIN. N*DTA represents the interaction between enterprise DTIN embedding and digital technology applications. Other variables are mentioned above.