Title
k-nearest neighbor Monte-Carlo control algorithm for POMDP-based dialogue systems
Abstract
In real-world applications, modelling dialogue as a POMDP requires the use of a summary space for the dialogue state representation to ensure tractability. Sub-optimal estimation of the value function governing the selection of system responses can then be obtained using a grid-based approach on the belief space. In this work, the Monte-Carlo control technique is extended so as to reduce training over-fitting and to improve robustness to semantic noise in the user input. This technique uses a database of belief vector prototypes to choose the optimal system action. A locally weighted k-nearest neighbor scheme is introduced to smooth the decision process by interpolating the value function, resulting in higher user simulation performance.
Year
Venue
Keywords
2009
SIGDIAL Conference
dialogue state representation,system response,belief space,monte-carlo control technique,summary space,pomdp-based dialogue system,optimal system action,belief vector prototype,value function,k-nearest neighbor monte-carlo control,modelling dialogue,higher user simulation performance,monte carlo,k nearest neighbor,optimal estimation
Field
DocType
Citations 
k-nearest neighbors algorithm,Monte Carlo method,Computer science,Partially observable Markov decision process,Interpolation,Bellman equation,Robustness (computer science),Artificial intelligence,Communication noise,Machine learning,Grid
Conference
3
PageRank 
References 
Authors
0.44
7
8
Name
Order
Citations
PageRank
Fabrice Lefèvre118526.62
M. Gašić2382.40
F. Jurčíček3351.90
S. Keizer4351.90
F. Mairesse5845.44
B. Thomson6553.63
Kai Yu7108290.58
S. Young81347.84