Prior of the Lexical model in the Hidden Vector State Parser

This paper describes an implementation of a statistical seman-tic parser for a closed domain with limited amount of training data. We implemented the hidden vector state model, which we present as a structure discrimination of a flat-concept model. The model was implemented in the graphical modeling toolkit. We introduced into the hidden vector state model a concept in-sertion penalty as a part of pattern recognition approach. In our model, the linear interpolation was used for both to deal with unseen words (unobserved input events) in training data and to smooth probabilities of the model. We evaluated the im-plementation of the concept insertion penalty in our model on a closed domain human-human train timetable dialogue corpus. We found that the concept insertion penalty was indispensable in our implementation of the hidden vector state model on the human-human train timetable dialogue corpus. Accuracy of the baseline system was increased from 33.7 % to 55.4%. 1