The present invention relates to a system and methodology providing
layered probabilistic representations for sensing, learning, and
inference from multiple sensory streams at multiple levels of temporal
granularity and abstraction. The methods facilitate robustness to subtle
changes in environment and enable model adaptation with minimal
retraining. An architecture of Layered Hidden Markov Models (LHMMs) can
be employed having parameters learned from stream data and at different
periods of time, wherein inferences can be determined relating to context
and activity from perceptual signals.