@InProceedings{janarthanam-lemon:2009:SIGDIAL, author = {Janarthanam, Srinivasan and Lemon, Oliver}, title = {A Two-Tier User Simulation Model for Reinforcement Learning of Adaptive Referring Expression Generation Policies}, booktitle = {Proceedings of the SIGDIAL 2009 Conference}, month = {September}, year = {2009}, address = {London, UK}, publisher = {Association for Computational Linguistics}, pages = {120--123}, url = {http://www.aclweb.org/anthology/W09-3916} }