TY - CHAP AU - Hüllermeier, Eyke AU - Fürnkranz, J. ED - Della Riccia, G. ED - Dubois, D. ED - Kruse, R. ED - Lenz, H.J. ID - 10185 T2 - Preferences and Similarities TI - Learning preference models from data: On the problem of label ranking and its variants ER -