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Title: Strategy Graphs for Influence Diagrams
An influence diagram is a graphical model of a Bayesian decision problem that is solved by finding a strategy that maximizes expected utility. When an influence diagram is solved by variable elimination or a related dynamic programming algorithm, it is traditional to represent a strategy as a sequence of policies, one for each decision variable, where a policy maps the relevant history for a decision to an action. We propose an alternative representation of a strategy as a graph, called a strategy graph, and show how to modify a variable elimination algorithm so that it constructs a strategy graph. We consider both a classic variable elimination algorithm for influence diagrams and a recent extension of this algorithm that has more relaxed constraints on elimination order that allow improved performance. We consider the advantages of representing a strategy as a graph and, in particular, how to simplify a strategy graph so that it is easier to interpret and analyze.  more » « less
Award ID(s):
1718384
PAR ID:
10387378
Author(s) / Creator(s):
; ;
Date Published:
Journal Name:
Journal of Artificial Intelligence Research
Volume:
75
ISSN:
1076-9757
Page Range / eLocation ID:
1177 to 1221
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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