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Cambridge Language Sciences

Interdisciplinary Research Centre


My research interests include speech recognition, synthesis and spoken dialogue systems. I am the inventor and original author of the HTK Toolkit for building hidden Markov model-based recognition systems (see, and I co-developed the original HTK large vocabulary speech recognition system which has figured strongly in DARPA/NIST evaluations since it was first introduced in the early nineties. More recently I have worked on statistical dialogue systems and pioneered the use of Partially Observable Markov Decision Processes for modelling them.  I also have industrial experience including four years working in the Apple Siri development team.


Key publications: 

J. Williams and S. Young (2007). Partially Observable Markov Decision Processes for Spoken Dialog Systems. Computer Speech and Language 21(2):231-422.

S. Young, M. Gasic, S. Keizer, F. Mairesse, J. Schatzmann, B. Thomson and K. Yu (2010). The Hidden Information State Model: a practical framework for POMDP-based spoken dialogue management. Computer Speech and Language, 24(2): 150-174.

F. Jurcicek, B. Thomson and S. Young (2012). Reinforcement learning for parameter estimation in statistical spoken dialogue systems. Computer Speech and Language, 26(3):127-228

S. Young (2010). Cognitive User Interfaces. IEEE Signal Processing Magazine,27(3): 128-140.

K. Yu and S. Young (2011). Continuous F0 Modelling for HMM based Statistical Parametric Speech Synthesis. IEEE Trans. Audio, Speech and Language Processing, to appear, 19(5):1071-1079.

Emeritus Professor of Information Engineering, Emmanuel College
Professor Steve  Young