  Recent interests in dynamic decision modeling have led to the development of
several representation and inference methods. These methods however, have
limited application under time critical conditions where a trade-off between
model quality and computational tractability is essential. This paper presents
an approach to time-critical dynamic decision modeling. A knowledge
representation and modeling method called the time-critical dynamic influence
diagram is proposed. The formalism has two forms. The condensed form is used
for modeling and model abstraction, while the deployed form which can be
converted from the condensed form is used for inference purposes. The proposed
approach has the ability to represent space-temporal abstraction within the
model. A knowledge-based meta-reasoning approach is proposed for the purpose of
selecting the best abstracted model that provide the optimal trade-off between
model quality and model tractability. An outline of the knowledge-based model
construction algorithm is also provided.
