Product-Service Systems (PSS): Bibliometric Analysis and Network Structure of Scientific Productions

In recent years, modern production enterprises for sustainable competitive advantage and profitability, consider the purpose of producing their products to provide services to customers instead of selling products or providing a combination and package of services and products. Product-service systems (PSS) are one of the dimensions of servitization. Therefore, considering the increasing use in the industry and the increased publication of articles in its various fields, such as the design, implementation, and business models of digital, intelligent, sustainable PSS, as well as little research in this field in the country, it is an excellent opportunity, especially for acquaintance and review of articles and studies is to identify gaps in the current literature. To achieve the goals, a comprehensive bibliometric analysis, and network structure has been performed on the literature available in the Scopus database until 7/18/2022.

The paper answers the main research questions on the published research on the PSS: (Q1) What is the main information, pattern, and trends of publication? (Q2) Who are the main authors? (Q3) Which are the most productive countries? (Q4), Which articles have the highest number of citations? (Q5) Which are the most productive institutions and universities in PSS? (Q6) Which are the main journals? (Q7) What are the most frequently used keywords? (Q8) What are the patterns of the Co-Citation network and citation analysis and trends? (Q9) What is the collaboration (Co-Authorship) network among organizations, authors, and countries? (Q10) What is the Co-Occurrence network? (Q11) What are the main clusters? Moreover, what are their subjects and issues? What are the trends of research on PSS? (Q12), and What are the research gaps? (Q13).

This section aims to summarize the available literature review in PSS to clarify the need for the present research.
Our literature review shows that PSS has increased in recent years. This increasing trend illustrates that PSS has attracted the attention of many academics and researchers. Although this field is crucial for modern firms, fewer studies have addressed PSS by scientometrics and bibliometric analysis. Therefore, it is vital to review these papers using bibliometric tools and specify gaps in the literature.
Figure 1 shows the annual publication trends and collaborations until 2022.
Figure 1: Figure 1 Literature published in the PSS field from 2000 to 2022 

This paper uses network structure, scientometrics, and descriptive analysis to analyze publications around the Product-service systems (PSS).
The present study uses "VOSviewer" software and open source R package "bibliometrix". Also, co-citation, collaboration (co-authorship), co-occurrence, citation, thematic mapping analysis, and clustering are discussed. The data collection came from the Scopus database.

The results show that the most dominant keywords are "product-service systems", "sustainability" and "PSS". The main common keywords in the leading cluster are PSS and servitization. The results show that most studies and citations are limited to developed economies such as China, England, and Italy. In addition, resources can be classified into four clusters. "Conceptualization and lexicography", "PSS design and implementation", "PSS integration and sustainability and connection with the supply chain" and "Digital and intelligent PSS".
Figure 2: Major keywords (WordCloud). source: findings of the present research 
Figure 3: Co-authorship network, source: findings of the present research 
Figure 4 displays the countries' collaboration networks.
Figure 4: Country Co-authorship network, source: findings of the present research 
The most cited papers globally are shown in Table 1.
Table 1: Most cited papers (global)
Paper
Total Citations
per Year s
Total Citation
Mont ok, 2002, j clean prod
67/ 1905
1411
Tukker a, 2004, bus strategy environ
73/ 2632
1392
Baines ts, 2007, proc inst mech eng part b j eng manuf
84/ 375
1350
Tukker a, 2015, j clean prod
114/ 5
916
Meier h, 2010, cirp ann manuf technol
54/ 2308
705
Tukker a, 2006, j clean prod
37/ 0588
630
Manzini e, 2003, j clean prod
24/ 1
482
Aurich jc, 2006, j clean prod
28/ 0588
477
Reim w, 2015, j clean prod
56/ 125
449
Beuren fh, 2013, j clean prod
39/ 1
391

This paper provides a network structure analysis and scientometrics of the trends in the field of PSS (2000–2022), using the Scopus and WOS databases. By comparing the search results in the two databases, 504 Scopus articles published in English were selected. We analyze and visualize with VOSviewer and Bibliometrix. Although there are several articles that have reviewed PSS, few have used a scientometrics approach in the PSS. This paper analyzed the most cited articles, the most productive authors and countries and frequent keywords and journals, the publication trends, and the most productive affiliations. This paper also conducted bibliometric analysis on Co-citation, Collaboration (Co-Authorship), Co-word (Co-Occurrence) analysis, citation, Thematic mapping, bibliographic coupling, and Clustering analysis. The results indicate a fast increase in the number of publications in recent years in the PSS. The analysis determines that “Ming x”, and “Sakao t” are the most productive authors in developing PSS. (Mont ok., 2002) is the most cited (global) article with 1411 citations
The important keywords are “product-service systems”, “product design” and “Product service system (PSS)”.

PSS is rapidly developing in servitization and can operate as a new opportunity for countries and companies. This paper proposes a systematic view of how the PSS field. The results show that the studies conducted are limited to developed economies such as the United Kingdom, Italy, China, and Germany.
Furthermore, the study suggests suggestions for future research through identifying the literature gaps by ThematicMap analysis and helps scholars find research opportunities and propose some practical implications. This paper offers managers an opportunity to familiarize themselves with the design and implementation of PSS.
The most dominant keywords are sustainability, servitization, product service systems, business models, and circular economy. The main common keywords in the leading cluster include "business model" and "service-product systems", "circular economy", and "conceptual design". Based on the results of the clustering analysis, the issues of serviceability, product design, and service-product systems are among the most important main clusters. This paper also provides suggestions for future research and helps researchers by identifying gaps in the literature review by schematic map analysis. Based on the gaps, the most important of them are communication and implementation using technologies such as industry 4.0 and blockchain technology and intelligence, quantification of criteria and how to implement them, development of quantitative business models and smart product-service systems, and, how to implement and design its supply chain, define and develop new criteria, and the connection and application of new technology in this field were proposed.