1. Computer Science Department, Bar Ilan University, Israel
2. Allen Institute for Artificial Intelligence, United States. yanaiela@gmail.com
3. Center for Information and Language Processing (CIS), LMU Munich, Germany. kassner@cis.lmu.de
4. Allen Institute for Artificial Intelligence, United States. shauli.ravfogel@;gmail.com
5. Language Technologies Institute, Carnegie Mellon University, United States. aravicha@cs.cmu.edu
6. Language Technologies Institute, Carnegie Mellon University, United States. hovy@cs.cmu.edu
7. Center for Information and Language Processing (CIS), LMU Munich, Germany
8. Allen Institute for Artificial Intelligence, United States. yoav.goldberg@gmail.com