Pointless Form of Rough Sets

  • FEIZABADI, ABOLGHASEM KARIMI (Department of Mathematics, Gorgan Branch, Islamic Azad University) ;
  • ESTAJI, ALI AKBAR (Faculty of Mathematics and Computer Sciences, Hakim Sabzevari University) ;
  • ABEDI, MOSTAFA (Faculty of Mathematics and Computer Sciences, Hakim Sabzevari University)
  • Received : 2013.11.27
  • Accepted : 2014.05.28
  • Published : 2015.09.23


In this paper we introduce the pointfree version of rough sets. For this we consider a lattice L instead of the power set P(X) of a set X. We study the properties of lower and upper pointfree approximation, precise elements, and their relation with prime elements. Also, we study lower and upper pointfree approximation as a Galois connection, and discuss the relations between partitions and Galois connections.


rough set;frame;prime element;lower and upper approximations;precise elements;Galois connection


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