Department of Engneering "Enzo Ferrari;
" University of Modena and Reggio Emilia;
Modena 41125;
Italy;
High Performance Computing Laboratory;
Institute of Information Science and Technologies of the Italian National Research Council (ISTI-CNR);
Pisa 56124;
Italy;
Department of Computer Science;
University ofBari Aldo Moro;
Bari 70125;
Italy;
Knowledge Discovery and Data Mining Laboratory;
ISTI-CNR;
Pisa 56127;
Italy;
Big Data Laboratory;
National Interuniversity Consortium for Informatics;
Rome 00185;
Italy;
Department of Statistics and Quantitative Methods;
University of Milano-Bicocca;
Milan 20126;
Italy;
Department of Computer Science;
Systems and Communications;
University of Milano-Bicocca;
Milan 20126;
Italy;
Department of Computer 5denee;
University of Pisa;
Pisa 56127;
Italy;
