REPORT dimitrakakis:rr05-29/IDIAP Gradient estimates of return Dimitrakakis, Christos Bengio, Samy EXTERNAL https://publications.idiap.ch/attachments/reports/2005/dimitrakakis-idiap-rr-05-29.pdf PUBLIC Idiap-RR-29-2005 2005 IDIAP Published in PASCAL Workshop in Principled Methods of Trading Exploration and Exploitation, London, UK, 2005 The exploration-exploitation trade-off that arises when one considers simple point estimates of expected returns no longer appears when full distributions are considered. This work develops a simple gradient-based approach for mainting such distributions and investigates methods for using them to direct exploration.