On Triangulating Dynamic Graphical Models

This paper introduces improved methodology to triangulate dynamic graphical models and dynamic Bayesian networks (DBNs). In this approach, a standard DBN template can be modified so the repeating and unrolled graph section may dissect the original DBN time slice and may also span (and partially intersect) many such slices. We introduce the notion of a “boundary” which divides a graph into multi-slice partitions each of which has an interface, and define the “boundary algorithm”, a method to find the best boundary (and corresponding interface) between partitions in such models. We prove that, after using this algorithm, the sizes of the best forwardand backward- interface (and also the corresponding fill-ins) are identical. The boundary algorithm allows for constrained elimination orders (and therefore graph triangulations) that are impossible using standard slice-by-slice constrained elimination. We describe the above using the Graphical Model ToolKit (GMTK)’s notion of ...

• Type: Conference
• Year: 2003
• Where: UAI
• Authors: Jeff A. Bilmes, Chris Bartels
• Keywords: Boundary Algorithm, Dynamic Graphical Model, Standard Dbn Templates, UAI 2003, UAI 2008