Title: Training Recurrent Networks Authors: Morten With Pedersen CONNECT, Department of Mathematical Modelling, Building 321 Technical University of Denmark DK-2800 Lyngby, Denmark Phones: + 45 45253920 Fax: + 45 45872599 email: mwp@imm.dtu.dk Abstract: Training recurrent networks is generally believed to be a difficult task. Excessive training times and lack of convergence to an acceptable solution are frequently reported. In this paper we seek to explain the reason for this from a numerical point of view and show how to avoid problems when training. In particular we investigate ill-conditioning, the need for and effect of regularization and illustrate the superiority of second-order methods for training. Extended summary version, submnitted for NNSP'97, Florida, September, 1997.