Research Article

Extended Tolerance Relation to Define a New Rough Set Model in Incomplete Information Systems

Table 4

Properties of approximations based on the three definitions.

PropertiesSingletonSubsetConcept

1a
1b
2a
2b
3a
3b
4a
4b
5a
5b
6a
6b
7a
7b
7c
7d
8a =
8b =

” indicates that the property is satisfied. and are lower and upper approximations that can be defined by singleton, subset, and concept methods.
X: denotes a complementary set of .