International Journal of Man-Machine Studies
Twofold fuzzy sets and rough sets—Some issues in knowledge representation
Fuzzy Sets and Systems
Uncertainty, belief, and probability
Computational Intelligence
When upper probabilities are possibility measures
Fuzzy Sets and Systems - Special issue dedicated to Professor Claude Ponsard
Interpretations of belief functions in the theory of rough sets
Information Sciences: an International Journal - From rough sets to soft computing
Extensions and intentions in the rough set theory
Information Sciences: an International Journal
Relational interpretations of neighborhood operators and rough set approximation operators
Information Sciences—Informatics and Computer Science: An International Journal
Rough set approach to incomplete information systems
Information Sciences: an International Journal
On Databases with Incomplete Information
Journal of the ACM (JACM)
The necessity of the strong &agr;-cuts of a fuzzy set
International Journal of Uncertainty, Fuzziness and Knowledge-Based Systems - Special issue on aggregation operators
A comparative study of fuzzy rough sets
Fuzzy Sets and Systems
Interval-Set Algebra for Qualitative Knowledge Representation
ICCI '93 Proceedings of the Fifth International Conference on Computing and Information
On the Unknown Attribute Values in Learning from Examples
ISMIS '91 Proceedings of the 6th International Symposium on Methodologies for Intelligent Systems
A novel approach to fuzzy rough sets based on a fuzzy covering
Information Sciences: an International Journal
Joint propagation of probability and possibility in risk analysis: Towards a formal framework
International Journal of Approximate Reasoning
Measuring roughness of generalized rough sets induced by a covering
Fuzzy Sets and Systems
Higher order models for fuzzy random variables
Fuzzy Sets and Systems
Covering Based Approaches to Rough Sets and Implication Lattices
RSFDGrC '09 Proceedings of the 12th International Conference on Rough Sets, Fuzzy Sets, Data Mining and Granular Computing
Similarity relations and fuzzy orderings
Information Sciences: an International Journal
Lower and upper approximations in data tables containing possibilistic information
Transactions on rough sets VII
On generalizing rough set theory
RSFDGrC'03 Proceedings of the 9th international conference on Rough sets, fuzzy sets, data mining, and granular computing
Fuzzy Rough Sets: The Forgotten Step
IEEE Transactions on Fuzzy Systems
Covering based rough set approximations
Information Sciences: an International Journal
Duality, conjugacy and adjointness of approximation operators in covering-based rough sets
International Journal of Approximate Reasoning
Characteristic matrix of covering and its application to Boolean matrix decomposition
Information Sciences: an International Journal
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Rough sets are often induced by descriptions of objects based on the precise observations of an insufficient number of attributes. In this paper, we study generalizations of rough sets to incomplete information systems, involving imprecise observations of attributes. The precise role of covering-based approximations of sets that extend the standard rough sets in the presence of incomplete information about attribute values is described. In this setting, a covering encodes a set of possible partitions of the set of objects. A natural semantics of two possible generalisations of rough sets to the case of a covering (or a non transitive tolerance relation) is laid bare. It is shown that uncertainty due to granularity of the description of sets by attributes and uncertainty due to incomplete information are superposed, whereby upper and lower approximations themselves (in Pawlak's sense) become ill-known, each being bracketed by two nested sets. The notion of measure of accuracy is extended to the incomplete information setting, and the generalization of this construct to fuzzy attribute mappings is outlined.