# Evolution of China's Building Energy Service Industry Based on Synergetic Theory
## 3 Research Methodology  
Given that this paper primarily determines the driving force of the BESI and the analysis of the industry's evolutionary phases, it is necessary to set this analysis within the context of the wider research methodology informing the study (Figure 1). Phase 1 focuses on the BESI system's establishment, dividing it into several subsystems. According to synergetic theory, it is the order parameter guiding the evolution of the BESI. Phase 2 attempts to identify the order parameter based on the literature review and determine the main order parameters. Phase 3 analyzes the BESI's evolution based on the results gained in phase 2. The central part of this paper is Phase 2, which concentrates on the order parameters' selection and the point-scoring phase within the context of earlier work that discussed models' development and weighting. The simplified logical sequence of the empirical study is shown in Figure 2. First, the BESI system--consisting of several sub-systems--is structured, and the order parameters in the BESI system are identified. Then, the order parameter in the whole system is evaluated utilizing the Decision-Making Trial and Evaluation Laboratory (DEMATEL) method. The DEMATEL is primarily used for assessing the cause-and-effect relationship between the problem criteria by producing a digraph and a cause-and-effect diagram that shows the influence of each factor on another [33; 34]. Clustering analysis was also conducted to categorize the determined order parameters. Based on the analysis and findings, several suggestions will be proposed to boost the development of the BESI. To obtain the required data and verify the results, a three-stage data collection approach is applied in this research. Firstly, based on the BESI system established according to the synergetic theory, the literature regarding energy services was thoroughly reviewed to preliminarily identify order parameters. Secondly, the first round of semi-structured interviews was implemented. It aimed to verify the preliminarily identified order parameters in the BESI system and gain an in-depth understanding of the BESI in the Chinese context. The interviewees were selected based on the following principle: they had either rich practical or academic experience in the BESI field. Academics were shortlisted based on their publication profiles in the energy service, building energy service, and energy conservation fields; their reputations at national and international levels; and their research statuses, whilst the professionals represented a diverse mix of policy-makers/legislators, ESCOs, and end-users. To obtain representative data from across these sectors, the panels needed to be robust in terms of both the number and quality of the personnel. A total of 15 interviewees were selected. These interviewees included professors, lecturers, managers, Ph.D. candidates, employees, and so forth. During the interview, the interviewees were asked to: (1) check the preliminary list of order parameters in the BESI system; (2) introduce the history, status quo, and their perceived future development of the BESI in the Chinese context; and (3) answer a series of open-ended questions regarding the BESI. Figure 1: Methodological approach. The third stage of data collection was to gain the required information for performing the DEMATEL approach. According to [PERSON], [PERSON], and [PERSON] [35], engaging group meetings can abate personal bias to the greatest extent. To circumvent the flaws of questionnaire surveys, a focus group was formed to obtain DEMATEL data. The members of the group meeting were also selected based on the above-mentioned principle. During the group meeting, the connotations of each order parameter were clearly illustrated to ensure 10 participants could hold a similar understanding of the parameters. Then, the participants were required to jointly answer the following queries: (1) can one parameter exert a direct influence on another parameter, and (2) what is the degree of this influence?