RT journal article T1 Decision Making in Fuzzy Rough Set Theory A1 Chacón Gómez, Fernando A1 Cornejo Piñero, María Eugenia A1 Medina Moreno, Jesús A2 Matemáticas K1 fuzzy rough set theory K1 decision rules K1 classification methods AB Decision rules are powerful tools to manage information and to provide descriptions of data sets; as a consequence, they can acquire a useful role in decision-making processes where fuzzy rough set theory is applied. This paper focuses on the study of different methods to classify new objects, which are not considered in the starting data set, in order to determine the best possible decision for them. The classification methods are supported by the relevance indicators associated with decision rules, such as support, certainty, and credibility. Specifically, the first one is based on how the new object matches decision rules that describe the data set, while the second one also takes into account the representativeness of these rules. Finally, the third and fourth methods take into account the credibility of the rules compared with the new object. Moreover, we have shown that these methods are richer alternatives or generalize other approaches given in the literature. PB Multidisciplinary Digital Publishing Institute (MDPI) SN 2227-7390 YR 2023 FD 2023 LK http://hdl.handle.net/10498/32049 UL http://hdl.handle.net/10498/32049 LA eng DS Repositorio Institucional de la Universidad de Cádiz RD 10-may-2026