Aysegul Caksu GulerEsra Dalan YildirimOya Bedre Ozbakir2025-10-0620221300-009810.55730/1300-0098.3150http://dx.doi.org/10.55730/1300-0098.3150https://gcris.yasar.edu.tr/handle/123456789/7151In this paper we generalize the notations of rough sets based on the topological space. Firstly we produce various topologies by using the concept of ideal Cj -neighbourhoods and Pj -neighbourhoods. When we compare these topologies with previous topologies we see that these topologies are more general. Then we introduce new methods to find the approximations by using these generated topologies. When we compare these methods with the previous methods we see that these methods are more accurate.EnglishTopological spaces, ideals, rough sets, 3C(j)-approximations, 3P(j)-approximationsSETSArticle