R. Li and L.M. Pereira. What is believed is what is explained. In H. Shrobe and T. Senator, editors, Proc. 13th Nat. Conf. on Arti cial Intelligence (AAAI'96), pages 550-555, Portland, 1996. AAAI Press/MIT Press.  Home/Search   Document Not in Database   Summary   Related Articles   Check

....is, when their degree of priority is greater than those of changes) this definition can be rephrased as: we consider the minimal set of changes needed to explain the observations. This is similar to the principle of actions to explain observation , which is studied in reasoning about actions [ Li and Pereira, 1996; Baral et al. 1996; McIlraith, 1998 ] There are two possible ways for defining the models of a knowledge base. We call these two possible semantics backward and pointwise. The first one is the simplest to explain, and allows for expressing scenarios in which knowledge at later time may rule ....

R. Li and L. Pereira. What is believed is what is explained. In Proc. of AAAI'96, pages 550--555, 1996.

....(that is, when their degree of priority is greater than those of changes) this definition can be rephrased as: consider the minimal set of changes needed to explain the observations. This is similar to the principle of actions to explain observation , which is studied in reasoning about actions [9, 2, 14]. There are two possible ways for defining the models of a knowledge base. We call these two possible semantics backward and pointwise. The first one is the simplest to explain, and allows for expressing scenarios in which knowledge at later time may rule out some initial models. The second one ....

R. Li and L. Pereira. What is believed is what is explained. In Proceedings of the Thirteenth National Conference on Artificial Intelligence (AAAI'96), pages 550--555, 1996.

....induces an ordering in a natural way: I # # J if and only if # # (I) # # # (J) One way to define the update is # #GU = Form(min(Mod( # # ) that is, the models of the result are the models of whose rank # # is minimal. 2. 6 Possible Causes Approach This approach was proposed in [ Li and Pereira, 1996 ] and is based upon the idea that changes in the world are caused by actions. Thus, update can be formalized with ad hoc languages such as A (introduced in [ Gelfond and Lifschitz, 1993 ] with an appropriate semantics. The main di#erence between reasoning about actions and belief update ....

....e#ect, and happens propositions. Given a domain description D, it may happen that new information, represented by a holds proposition H , has to be incorporated. Due to the lack of space, we cannot introduce formally the semantics of A neither that of the belief update based on it. We refer to [ Li and Pereira, 1996 ] where the update is introduced, for a more detailed explanation. The new holds proposition H could be not implied by D. In this case, we must find an explanation, i.e. a possible cause of the change. Formally, an explanation is a set of happens and initially propositions P such that D # P ....

[Article contains additional citation context not shown here]

R. Li and L. Pereira. What is believed is what is explained. In Proc. of AAAI-96, pages 550--555, 1996.

....In Section 5 we compare our work with other belief revision update operations, namely, possible worlds approach PWA [Gin 86] and possible models approach PMA [Win 88] In the final section we conclude this paper with a summary and some remarks. A short version of this paper was published in [LP 96A] 1 Domain description In this section we will briefly introduce Gelfond and Lifschitz action description language A [GL 93] to describe domains of actions. Domain descriptions will act as cause effect constraints in our methodology for knowledge representation and assimilation. 1.1 Syntax ....

Li, R. and Pereira, L. M., What is believed is what is explained (sometimes) , Proc. of AAAI'96, pp. 550 -- 555

....and enhancements of A CO remain to be analyzed and done in future. Currently, extensive and intensive discussions on various diagnosis problems with domains of actions are also under investigation. Related work on belief update in action domains is also in progress and is partially reported in [38]. In addition, we are also working on a multi agent description language based on A CO for a group of autonomous hysteretic agents in a dynamic world. Acknowledgements This work was supported by the JNICT PROLOPPE project under PRAXIS 3 31 TIT 24 94, and a post doctoral fellowship from JNICT ....

Li, R. and Pereira, L. M., What is believed is what is explained (sometimes), Proc. of AAAI-- 96, 1996

....domain description which enables us to generate plan, to predict the future, or to explain the past, as what we expected and intended. 7 Concluding Remarks In this paper we have presented an experiment on using the abductive logic programming paradigm to refine an action theory in line with [11, 12] starting from [7] An action theory, also called domain description, describes effects of actions and initial states in a dynamic domain. A complete action theory should enable us to determine which fluent will be true and which fluent will be false after an action is performed. A complete action ....

R. Li and L.M. Pereira. What is believed is what is explained (sometimes). In Proc. of AAAI'96, pages 550--555, 1996.

....domain description which enables us to generate plan, to predict the future, or to explain the past, as what we expected and intended. 7 Concluding Remarks In this paper we have presented an experiment on using the abductive logic programming paradigm to refine an action theory in line with [10, 11] starting from [6] An action theory, also called domain description, describes effects of actions and initial states in a dynamic domain. A complete action theory should enable us to determine which fluent will be true and which fluent will be false after an action is performed. A complete action ....

R. Li and L.M. Pereira. What is believed is what is explained (sometimes) . In Proc. of AAAI'96, pages 550--555, 1996.

....4 . For fluents which can be changed by other agents in multi agent systems, when there is a discrepancy between the sensed data and inferred data, then the agent will take a so called possible causes approach PCA to knowledge assimilation [8] The possible causes approach was first proposed in [11] in the context of simple action domains in contrast to the possible worlds approach PWA [6] and the possible models approach PMA [21] and then was generalized for concurrent actions in [12] A possible cause of new knowledge consists of some abduced occurrences of actions performed by other ....

Li, R. and Pereira, L. M., What is believed is what is explained (sometimes), Proc. of AAAI'96, American National Conference on Artificial Intelligence, 1996, pp. 550 -- 555

....to their domain descriptions. In particular, in contrast to Ginsberg s possible worlds approach (PWA) and Winslett s possible models approach (PMA) we propose a possible causes approach (PCA) to updates of temporal knowledge based on the slogan: What is believed is what is explained, advocated in [9]. A possible cause of new knowledge consists of abduced occurrences of actions and value propositions about the initial state of the domain of actions, that would allow to derive the new knowledge, and can be computed with abductive logic programming. 1 Introduction Suppose that we have a ....

....to domains of actions, where there is a clear cause effect relation. In domains of actions, new knowledge is about changes in truth values of fluents. The possible causes for changes in truth values of fluents are the occurrences of actions. The possible causes approach was originally proposed in [9] in a simple domain of actions. The advantage of the PCA approach over the PWA and PMA approaches are also discussed in [9] In this paper we will generalize the results in [9] to accomodate concurrent actions. We will follow [8] to discuss fluents in a three valued setting but logic programs are ....

[Article contains additional citation context not shown here]

Li, R. and Pereira, L. M., What is believed is what is explained (sometimes), AAAI'96-American Thirteenth National Conf. on Artificial Intelligence, Portland, Oregon, August 4 - 8, 1996

....domain description which enables us to generate plan, to predict the future, or to explain the past, as what we expected and intended. 7 Concluding Remarks In this paper we have presented an experiment on using the abductive logic programming paradigm to refine an action theory in line with [10, 11] starting from [6] An action theory, also called domain description, describes effects of actions and initial states in a dynamic domain. A complete action theory should enable us to determine which fluent will be true and which fluent will be false after an action is performed. A complete action ....

R. Li and L.M. Pereira. What is believed is what is explained (sometimes) . In Proc. of AAAI'96, pages 550--555, 1996.

No context found.

R. Li and L.M. Pereira. What is believed is what is explained. In H. Shrobe and T. Senator, editors, Proc. 13th Nat. Conf. on Arti cial Intelligence (AAAI'96), pages 550-555, Portland, 1996. AAAI Press/MIT Press.

No context found.

Li, R., and Pereira, L. 1996. What is believed is what is explained. In Proc. AAAI'96, 550--555. AAAI Press/MIT Press.

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