The Role of Roles in Classifying Annotated Biomedical Text Son Doan author Ai Kawazoe author Nigel Collier author 2007-06 text Biological, translational, and clinical language processing K Bretonnel Cohen editor Dina Demner-Fushman editor Carol Friedman editor Lynette Hirschman editor John Pestian editor Association for Computational Linguistics Prague, Czech Republic conference publication doan-etal-2007-role https://aclanthology.org/W07-1003/ 2007-06 17 24