An evolutionary graph of product service system research topics based on bibliometric analysis and topic modelling

Existing product service system (PSS)-related reviews rarely probe into the evolution of PSS-related research topics, leaving it difficult for researchers to grasp the development process of PSS research. The current study, by constructing an evolutionary graph of PSS research topics, aims to elucidate the development process of PSS research. Bibliometric analysis and topic modelling have been combined to construct the evolutionary graph of PSS research topics for 2753 records from 2000 to 2023. The clustering and time-zone graphs of co-occurring keywords have been constructed using the Citespace tool to determine four PSS research fields. The research topics have been mined from the abstracts in each year's corpus via the Latent Dirichlet Allocation (LDA) algorithm. The labels of each research topic have been determined by analysing the distribution of topic words in combination with emerging keywords. Each topic label has been assigned to the corresponding research field, resulting in an evolutionary graph of PSS research topics. Then, each evolutionary route has been summarised and analysed in detail. The outcomes reveal that digital and smart technologies have a profound impact on PSS. On this basis, several PSS research agendas are proposed for future studies.