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Interpretation as Abduction
, 1990
"... An approach to abductive inference developed in the TACITUS project has resulted in a dramatic simplification of how the problem of interpreting texts is conceptualized. Its use in solving the local pragmatics problems of reference, compound nominals, syntactic ambiguity, and metonymy is described ..."
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Cited by 687 (38 self)
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An approach to abductive inference developed in the TACITUS project has resulted in a dramatic simplification of how the problem of interpreting texts is conceptualized. Its use in solving the local pragmatics problems of reference, compound nominals, syntactic ambiguity, and metonymy is described and illustrated. It also suggests an elegant and thorough integration of syntax, semantics, and pragmatics. 1
Evaluation of Explanatory Hypotheses
, 1991
"... Abduction is often viewed as inference to the "best" explanation. However, the evaluation of the goodness of candidate hypotheses remains an open problem. Most artificial intelligence research addressing this problem has concentrated on syntactic criteria, applied uniformly regardless of t ..."
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Cited by 20 (9 self)
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Abduction is often viewed as inference to the "best" explanation. However, the evaluation of the goodness of candidate hypotheses remains an open problem. Most artificial intelligence research addressing this problem has concentrated on syntactic criteria, applied uniformly regardless of the explainer's intended use for the explanation. We demonstrate that syntactic approaches are insufficient to capture important differences in explanations, and propose instead that choice of the "best" explanation should be based on explanations' utility for the explainer 's purpose. We describe two classes of goals motivating explanation: knowledge goals reflecting internal desires for information, and goals to accomplish tasks in the external world. We describe how these goals impose requirements on explanations, and discuss how we apply those requirements to evaluate hypotheses in two computer story understanding systems. In order to learn from experience, a reasoner must be able to explain what...
Aqua: Questions that drive the explanation process
, 1994
"... In the doctoral dissertation from which this chapter is drawn, Ashwin Ram presented an alternative perspective on the processes of story understanding, explanation, and learning. The issues that Ram explores in that dissertation are similar to those that are explored by the other authors in this boo ..."
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Cited by 15 (1 self)
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In the doctoral dissertation from which this chapter is drawn, Ashwin Ram presented an alternative perspective on the processes of story understanding, explanation, and learning. The issues that Ram explores in that dissertation are similar to those that are explored by the other authors in this book, but the angle that Ram takes on these issues is somewhat different. Ram's exploration of
Adaptive Similarity Assessment for Case-Based Explanation
- INTERNATIONAL JOURNAL OF EXPERT SYSTEMS RESEARCH AND APPLICATIONS
, 1995
"... Guiding the generation of abductive explanations is a difficult problem. Applying casebased reasoning to abductive explanation generation---generating new explanations by retrieving and adapting explanations for prior episodes---offers the benefit of re-using successful explanatory reasoning but rai ..."
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Cited by 10 (4 self)
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Guiding the generation of abductive explanations is a difficult problem. Applying casebased reasoning to abductive explanation generation---generating new explanations by retrieving and adapting explanations for prior episodes---offers the benefit of re-using successful explanatory reasoning but raises new issues concerning how to perform similarity assessment to judge the relevance of prior explanations to new situations. Similarity assessment affects two points in the case-based explanation process: deciding which explanations to retrieve and evaluating the retrieved candidates. We address the problem of identifying similar explanations to retrieve by basing that similarity assessment on a categorization of anomaly types. We show that the problem of evaluating retrieved candidate explanations is often impeded by incomplete information about the situation to be explained, and address that problem with a novel similarity assessment method which we call constructive similarity assessme...
AD-A259 608 f Interpretation as Abduction
"... Abduction is inference to the best explanation. In the TACITUS project at SRI we have developed an approach to abductive inference, called "weighted abduction", that has resulted in a significant simplification of how the problem of interpreting texts is conceptualized. The interpretation ..."
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Abduction is inference to the best explanation. In the TACITUS project at SRI we have developed an approach to abductive inference, called "weighted abduction", that has resulted in a significant simplification of how the problem of interpreting texts is conceptualized. The interpretation of a text is the minimal explanation of why the text would be true. More precisely, to interpret a text, one must prove the logical form of the text from what is already mutually known, allowing for coercions, merging redundancies where possible, and making assumptions where necessary. It is shown how such "local pragmatics " problems as reference resolution, the interpretation of compound nominals, the resolution of syntactic ambiguity and metonymy, and schema recognition can be solved in this manner. Moreover, this approach of "interpretation as abduction " can be combined with the older view of "parsing as deduction " to produce an elegant and thorough integration of syntax, semantics, and pragmatics, one that spans the range of linguistic phenomena from phonology to discourse structure. Finally, we discuss means for making the abduction process efficient, possibilities for extending the approach to other pragmatics phenomena, and the semantics of the weights and costs in the abduction scheme. 1
PARSING = PARSIMONIOUS COVERING? (Abduction in Logical Form Generation) * Abstract
"... Many researchers believe that certain aspects of natural language processing, such as word sense disambiguation and plan recognition in stories, constitute abductive inferences. We have been working with a specific model of abduction, called parsimonious covering, applied in diagnostic problem solvi ..."
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Many researchers believe that certain aspects of natural language processing, such as word sense disambiguation and plan recognition in stories, constitute abductive inferences. We have been working with a specific model of abduction, called parsimonious covering, applied in diagnostic problem solving, word sense disambiguation and logical form generation in some restricted settings. Diagnostic parsimonious covering has been extended into a dualroute model to account for syntactic and semantic aspects of natural language. The two routes of covering are integrated by defining "open class " linguistic concepts, aiding each other. The diagnostic model has dealt with sets, while the extended version, where syntactic considerations dictate word order, deals with sequences of linguistic concepts. Here we briefly describe the original model and the extended version, and briefly characterize the notions of covering and different criteria of parsimony. Finally we examine the question of whether parsimonious covering can serve as a general framework for parsing. 1
Factors in Causal Explanation
"... The construction of explanations is a key process in human understanding, having many applications for internal tasks such as learning through to external tasks such as diagnosis and image interpretation. In this paper we introduce five orthogonal dimensions along which any explanation task can ..."
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The construction of explanations is a key process in human understanding, having many applications for internal tasks such as learning through to external tasks such as diagnosis and image interpretation. In this paper we introduce five orthogonal dimensions along which any explanation task can be characterised and show how their identification gives rise to a new model of explanation construction and evaluation. The identification of these dimensions is important because any system that attempts to model the explanation capability of humans must incorporate some notion of each dimension. In addition the dimensions help to identify the type of knowledge human reasoners and hence any commonsense reasoning system must possess. We argue that the flexibility of the explanation process introduced above means that backward chaining algorithms from the event to be explained should still be an important topic of research in AI. Introduction A diverse set of intelligent act...
Elsevier ARTINT 1059 Interpretation as abduction
"... have developed an approach to abductive inference, called "weighted abduction", that has resulted in a significant simplification of how the problem of interpreting texts is conceptualized. The interpretation of a text is the minimal explanation of why the text would be true. More ..."
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have developed an approach to abductive inference, called "weighted abduction", that has resulted in a significant simplification of how the problem of interpreting texts is conceptualized. The interpretation of a text is the minimal explanation of why the text would be true. More precisely, to interpret a text, one must prove the logical form of the text from what is already mutually known, allowing for coercions, merging redundancies where possible, and making assumptions where necessary. It is shown how such "local pragmatics " problems as reference resolution, the interpretation of compound nominals, the resolution of syntactic ambiguity and metonymy, and schema recognition can be solved in this manner. Moreover, this approach of "interpretation as abduction " can be combined with the older view of "parsing as deduction " to produce an elegant and thorough integration of syntax, semantics, and pragmatics, one that spans the range of linguistic phenomena from phonology to discourse structure. Finally, we discuss means for making the abduction process efficient, possibilities for extending the approach to other pragmatics phenomena, and the semantics of the weights and costs in the abduction scheme. 1.
A Tractable Class of Abduction Problems Abstract
"... The problem of finding a set of assumptions which explain a given proposition is in general NP-hard, even when the background theory is an acyclic Horn theory. In this paper it is shown that when the background theory is acyclic Horn and its pseudo-completion is unit refutable, there is a polynomial ..."
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The problem of finding a set of assumptions which explain a given proposition is in general NP-hard, even when the background theory is an acyclic Horn theory. In this paper it is shown that when the background theory is acyclic Horn and its pseudo-completion is unit refutable, there is a polynomial time algorithm for finding minimal explanations. A test for unit-refutability of clausal theories is presented, based on the topology of the connection graph of the theory. 1
