A review of q-rung orthopair fuzzy information: bibliometrics and future directions

The q-rung orthopair fuzzy set (q-ROFS), initiated by Yager, is a novel tool to dispose of indeterminacy that considers the membership \(\mu\) and non-membership \(\nu\), which satisfy the limited condition \(0\le \mu ^q+\nu ^q\le 1\). It can be employed in characterizing the vague preference more precisely and flexibly than intuitionistic fuzzy set and Pythagorean fuzzy set. q-ROFS has attracted deep concern of numerous researchers, which is mainly distributed in diverse research points such as comparison methods, aggregation operators, decision making methods, calculus, information measure, preference relation, graph and application scenarios. As a result of this growth, we give an overview of q-ROFS for offering a clear perspective on novel trends. A total of 80 q-ROFS related publications of Web of Science are in-depth analysis. Some significant results related to annual trends, country level, institutional level, journal level, highly cited papers, and research landscape are generated and illustrated. Eighteen future research directions or challenges related to the q-ROFS theory are indicated. Finally, the co-authorship analysis, the co-citation analysis, the co-occurrence analysis and the bibliographic coupling analysis are derived by VOSviewer software.