Learning the structure of HMM's through grammatical inference techniques

• Published in: International Conference on Acoustics, Speech, and Signal Processing pp. 717 - 720 vol.2
• Main Authors: Casacuberta, F., Vidal, E., Mas, B., Rulot, H.
• Format: Conference Proceeding
• Language: English
• Published: IEEE 1990
• Subjects: Hidden Markov models; Inference algorithms; Speech recognition; Topology; Training data
• ISSN: 1520-6149; 2379-190X
• DOI: 10.1109/ICASSP.1990.115882

A technique is described in which all the components of a hidden Markov model are learnt from training speech data. The structure or topology of the model (i.e. the number of states and the actual transitions) is obtained by means of an error-correcting grammatical inference algorithm (ECGI). This structure is then reduced by using an appropriate state pruning criterion. The statistical parameters that are associated with the obtained topology are estimated from the same training data by means of the standard Baum-Welch algorithm. Experimental results showing the applicability of this technique to speech recognition are presented.< >