Summary: 6th International Symposium on Imprecise Probability: Theories and Applications, Durham, United Kingdom, 2009
Epistemic irrelevance in credal networks: the case of imprecise Markov trees
Gert de Cooman and Filip Hermans
SYSTeMS, Ghent University, Belgium
{gert.decooman,filip.hermans}@ugent.be
Alessandro Antonucci and Marco Zaffalon
IDSIA, Switzerland
{alessandro,zaffalon}@idsia.ch
Abstract
We replace strong independence in credal networks with
the weaker notion of epistemic irrelevance. Focusing on
directed trees, we show how to combine local credal sets
into a global model, and we use this to construct and justify
an exact message-passing algorithm that computes updated
beliefs for a variable in the tree. The algorithm, which is
essentially linear in the number of nodes, is formulated
entirely in terms of coherent lower previsions. We supply
examples of the algorithm's operation, and report an ap-
plication to on-line character recognition that illustrates the
advantages of our model for prediction.

Source: Antonucci, Alessandro - Istituto Dalle Molle di Studi sull'Intelligenza Artificiale (IDSIA)
Zaffalon, Marco - Istituto Dalle Molle di Studi sull' Intelligenza Artificiale (IDSIA)

Collections: Computer Technologies and Information Sciences