IQR: An interactive query relaxation system for the empty-answer problemDavide MottinAlice Marascuet al.2014SIGMOD 2014
A holistic and principled approach for the empty-answer problemDavide MottinAlice Marascuet al.2016VLDB Journal
A probabilistic optimization framework for the empty-answer problemDavide MottinAlice Marascuet al.2013VLDB