Henrik Grosskreutz Stefan Rüping Stefan Wrobel Tight Optimistic Estimates for Fast Subgroup Discovery. 440-456 2008 ECML/PKDD (1) http://dx.doi.org/10.1007/978-3-540-87479-9_47 conf/pkdd/2008-1 db/conf/pkdd/pkdd2008-1.html#GrosskreutzRW08