ABSTRACT
Definition 3.1 If decision table is S = (U, A, V, f ), and A = C ∪ D, C ∩ D = ϕ, then the rough membership function of the decision classes is
µX x I x X
I x ( ) | ( ) |
| ( ) | =
∩ (3.1)
Rough membership function μX(x) can be interpreted as conditional probability, and expressed as P(X/I(x)), and also it can be interpreted as the condence that x belongs to X. According to formula (3.1), rough membership function value is calculated from the data obtained, while the fuzzy set membership function is obtained by the subjective assumption.
