Title
A General Framework for Reason Maintenance
Abstract
There are several different kinds of reason-maintenance system in existence, which provide rather different functionalities. I present a general structure that subsumes most such systems, and that allows some new behaviors to emerge. The general framework is based on logic-style clauses (disjunctions of literals) instead of justifications. Literals are tagged with labels that say what assumption sets make them true and false. Nonmonotonicity is implemented by allowing clauses to contain disjuncts of the form L(p), which supports propagation through a clause whenever p is not known to be true. The resulting system supports two popular styles of dependency-directed backtracking, using nogoods and assumption retraction. Assumption retraction does not require a separate contradiction-elimination phase, but occurs automatically during label propagation. Label propagation can be achieved by the usual variants of Boolean constraint propagation, provided there are no "odd loops" through the clauses, and it can be shown that the system itself never creates odd loops.
Year
DOI
Venue
1991
10.1016/0004-3702(91)90017-E
Artif. Intell.
Field
DocType
Volume
Of the form,Inference,Label propagation,Computer science,Artificial intelligence,Reason maintenance,Unit propagation,Backtracking
Journal
50
Issue
ISSN
Citations 
3
0004-3702
24
PageRank 
References 
Authors
3.82
15
1
Name
Order
Citations
PageRank
Drew McDermott11743656.17