AN UNSUPERVISED FRAMEWORK
As an alternative to the preceding supervised approaches to social
state recognition and social skills execution, which require labelled
data, we have also developed a non-parametric Bayesian framework
for automatically inferring social states in an unsupervised manner
[13], which can be viewed as a natural fusion of multimodal observations.
This approach makes use of the infinite POMDP method [2],
which does not require advance knowledge of the size of the state
space, but rather lets the model grow to accommodate the data.