Division of Informatics

Forrest Hill & 80 South Bridge

## Research Paper #813 | |
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Title: | Constructing Probalistic Atms Using Extended Incidence Calculus |

Authors: | Liu,W; Bundy,A |

Date: | Jun 1996 |

Presented: | Accepted for publication in the Journal of Approximate Reasoning |

Keywords: | |

Abstract: | This paper discusses the relations between extended incidence calculus and assumption based truth maintenance systems (ATMSs). We first prove ;that managing labels for statements (nodes) in an ATMS is equivalent to producing incidence sets of these statements in extending incidence calculus. We then demonstrate that the justification set for a node is functionally equivalent to the implication relation set for the same node in extended incidence calculus. As a consequence, extended incidence calculus can provide justifications for an ATMS, becuase implication relation sets are discovered y the system automatically. We alos show that extended incidence calculus provides a theoretical basis for constructing a probabilistic ATMS by associating proper probability distributions on assumptions. In this way, we can not only produce labels for all nodes in the system, but also calculate the probability of any such nodes in it. The nogood environments can also be obtained automatically. Therefore, extended incidence calculus and the ATMS are ;equivalent in carrying out inferences at both the symbolic level and the numerical level. This extends a result due to Laskey and Lehner. |

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