Wróblewski J., 2005. Pairwise Cores in Information Systems. Proc. of RSFDGrC'2005, Regina, Canada. Springer-Verlag (LNAI 3641), Berlin, Heidelberg 2004, vol. 1, pp. 166 - 175
ABSTRACT
A core in information system is a set of attributes globally necessary to
distinct objects from different decision classes (i.e. the intersection of
all reducts of the information system). A notion of a pairwise core (2-core), which
naturally extends the definition of a core into the case of pairs of attributes
is presented. Some useful features concerned with the graph representation
of pairwise cores are discussed.
The paper presents also practical application of the notion of 2-core.
It is known that a core (if exists) may be used to improve the reduct
finding methods, since there exist polynomial algorithms for core construction.
The same may be proven for a 2-core, which may be also used for estimation of minimal
reduct size.