Title: Second-Order Methods in Boltzmann Learning: An Application to Speechreading Authors: Morten With Pedersen Section for Digital Signal Processing Department of Mathematical Modelling Technical University of Denmark B321 DK-2800 Lyngby, DENMARK mwp@imm.dtu.dk David G. Stork Machine Learning and Perception Group Ricoh Silicon Valley 2882 Sand Hill Road Suite 115 Menlo Park, CA 94025-7022 USA stork@crc.ricoh.com Abstract: We introduce second-order methods for training and pruning of general Boltzmann networks trained with cross-entropy error. In particular, we derive the second derivatives for the entropic cost function. We illustrate pruning on Boltzmann zippers, applied to real-world data --- a speechreading (lipreading) problem. Submitted for NIPS*97, Denver Colorado, December 1997.