Title
Duality, conjugacy and adjointness of approximation operators in covering-based rough sets.
Abstract
Many different proposals exist for the definition of lower and upper approximation operators in covering-based rough sets. In this paper, we establish relationships between the most commonly used operators, using especially concepts of duality, conjugacy and adjointness (also referred to as Galois connection). We highlight the importance of the adjointness condition as a way to provide a meaningful link, aside from duality, between a pair of approximation operators. Moreover, we show that a pair of a lower and an upper approximation operator can be dual and adjoint at the same time if and only if the upper approximation is self-conjugate, and we relate this result to a similar characterization obtained for the generalized rough set model based on a binary relation.
Year
DOI
Venue
2014
10.1016/j.ijar.2013.08.002
Int. J. Approx. Reasoning
Keywords
Field
DocType
generalized rough set model,covering-based rough set,upper approximation operator,binary relation,different proposal,upper approximation,adjointness condition,galois connection,meaningful link,approximation operator,rough sets
Galois connection,Discrete mathematics,Approximation operators,Binary relation,Conjugacy class,Rough set,Duality (optimization),If and only if,Operator (computer programming),Mathematics
Journal
Volume
Issue
ISSN
55
1
0888-613X
Citations 
PageRank 
References 
33
0.86
31
Authors
3
Name
Order
Citations
PageRank
Mauricio Restrepo1813.15
Chris Cornelis22116113.39
Jonatan Gómez324129.70