Theory contraction and base contraction unified

1993 ◽  
Vol 58 (2) ◽  
pp. 602-625 ◽  
Author(s):  
Sven Ove Hansson
Keyword(s):  
Contraction Operator ◽  
Partial Meet Contraction ◽  
Belief Base ◽  
Theory Contraction ◽  
Axiomatic Characterizations ◽  
Base Contraction ◽  
Belief Set

AbstractOne way to construct a contraction operator for a theory (belief set) is to assign to it a base (belief base) and an operator of partial meet contraction for that base. Axiomatic characterizations are given of the theory contractions that are generated in this way by (various types of) partial meet base contractions.

scholarly journals Shielded Base Contraction (Extended Abstract)

2019 ◽  
Author(s):  
Marco Garapa ◽  
Eduardo Fermé ◽  
Maurício D. L. Reis
Keyword(s):  
Contraction Operator ◽  
Belief Bases ◽  
Axiomatic Characterizations ◽  
Base Contraction

In this paper we study a kind of non-prioritized contraction operator on belief bases -known as shielded base contractions. We propose twenty different classes of shielded base contractions and obtain axiomatic characterizations for each one of them. Additionally we thoroughly investigate the interrelations (in the sense of inclusion) among all those classes.

Belief base contraction by belief accrual

2019 ◽  
Vol 275 ◽  
pp. 78-103
Author(s):  
Cristhian A.D. Deagustini ◽  
M. Vanina Martinez ◽  
Marcelo A. Falappa ◽  
Guillermo R. Simari
Keyword(s):  
Belief Base ◽  
Base Contraction

scholarly journals Kernel Contraction and Base Dependence

2017 ◽  
Vol 60 ◽  
pp. 97-148
Author(s):  
Mehrdad Oveisi ◽  
James P. Delgrande ◽  
Francis Jeffry Pelletier ◽  
Fred Popowich
Keyword(s):  
Belief Change ◽  
Dependence Relation ◽  
Specific Criterion ◽  
Strong Base ◽  
Belief Base ◽  
Dependence Relations ◽  
Kernel Contraction ◽  
Approximate Dependence ◽  
Information Finding ◽  
Belief Set

The AGM paradigm of belief change studies the dynamics of belief states in light of new information. Finding, or even approximating, those beliefs that are dependent on or relevant to a change is valuable because, for example, it can narrow the set of beliefs considered during belief change operations. A strong intuition in this area is captured by Gärdenfors’s preservation criterion (GPC), which suggests that formulas independent of a belief change should remain intact. GPC thus allows one to build dependence relations that are linked with belief change. Such dependence relations can in turn be used as a theoretical benchmark against which to evaluate other approximate dependence or relevance relations. Fariñas and Herzig axiomatize a dependence relation with respect to a belief set, and, based on GPC, they characterize the correspondence between AGM contraction functions and dependence relations. In this paper, we introduce base dependence as a relation between formulas with respect to a belief base, and prove a more general characterization that shows the correspondence between kernel contraction and base dependence. At this level of generalization, different types of base dependence emerge, which we show to be a result of possible redundancy in the belief base. We further show that one of these relations that emerge, strong base dependence, is parallel to saturated kernel contraction. We then prove that our latter characterization is a reversible generalization of Fariñas and Herzig’s characterization. That is, in the special case when the underlying belief base is deductively closed (i.e., it is a belief set), strong base dependence reduces to dependence, and so do their respective characterizations. Finally, an intriguing feature of Fariñas and Herzig’s formalism is that it meets other criteria for dependence, namely, Keynes’s conjunction criterion for dependence (CCD) and Gärdenfors’s conjunction criterion for independence (CCI). We prove that our base dependence formalism also meets these criteria. Even more interestingly, we offer a more specific criterion that implies both CCD and CCI, and show our base dependence formalism also meets this new criterion.

Theory contraction through base contraction

1991 ◽  
Vol 20 (2) ◽  
Author(s):  
Andr� Fuhrmann
Keyword(s):  
Theory Contraction ◽  
Base Contraction

Theory Contraction and Base Contraction Unified

2016 ◽  
pp. 219-245 ◽  
Author(s):  
Sven Ove Hansson
Keyword(s):  
Theory Contraction ◽  
Base Contraction

scholarly journals Axiomatic characterizations under players nullification

2016 ◽  
Vol 80 ◽  
pp. 47-57 ◽  
Author(s):  
Sylvain Béal ◽  
Sylvain Ferrières ◽  
Eric Rémila ◽  
Philippe Solal
Keyword(s):  
Axiomatic Characterizations

Mineral exploration with 3-D controlled-source electromagnetic method: a synthetic study of Sukhoi Log gold deposit

2019 ◽  
Vol 219 (3) ◽  
pp. 1698-1716 ◽  
Author(s):  
M Malovichko ◽  
A V Tarasov ◽  
N Yavich ◽  
M S Zhdanov
Keyword(s):  
Finite Difference ◽  
Gold Deposit ◽  
Large Scale ◽  
Mineral Exploration ◽  
Mineral Deposit ◽  
Hydrocarbon Exploration ◽  
Contraction Operator ◽  
Inversion Algorithm ◽  
Controlled Source ◽  
Regularized Inversion

SUMMARY This paper presents a feasibility study of using the controlled-source frequency-domain electromagnetic (CSEM) method in mineral exploration. The method has been widely applied for offshore hydrocarbon exploration; however, nowadays this method is rarely used on land. In order to conduct this study, we have developed a fully parallelized forward modelling finite-difference (FD) code based on the iterative solver with contraction-operator preconditioner. The regularized inversion algorithm uses the Gauss–Newton method to minimize the Tikhonov parametric functional with the Laplacian-type stabilizer. A 3-D parallel inversion code, based on the iterative finite-difference solver with the contraction-operator preconditioner, has been evaluated for the solution of the large-scale inverse problems. Using the computer simulation for a synthetic model of Sukhoi Log gold deposit, we have compared the CSEM method with the conventional direct current sounding and the CSEM survey with a single remote transmitter. Our results suggest that, a properly designed electromagnetic survey together with modern 3-D inversion could provide detailed information about the geoelectrical structure of the mineral deposit.

Effects of Players’ Nullification and Equal (Surplus) Division Values

2018 ◽  
Vol 20 (01) ◽  
pp. 1750029 ◽  
Author(s):  
Takumi Kongo
Keyword(s):  
The Other ◽  
Equal Division ◽  
Transferable Utility ◽  
Tu Games ◽  
Axiomatic Characterizations ◽  
The Difference ◽  
Monotonicity Axioms ◽  
Equal Surplus Division

We provide axiomatic characterizations of the solutions of transferable utility (TU) games on the fixed player set, where at least three players exist. We introduce two axioms on players’ nullification. One axiom requires that the difference between the effect of a player’s nullification on the nullified player and on the others is relatively constant if all but one players are null players. Another axiom requires that a player’s nullification affects equally all of the other players. These two axioms characterize the set of all affine combinations of the equal surplus division and equal division values, together with the two basic axioms of efficiency and null game. By replacing the first axiom on players’ nullification with appropriate monotonicity axioms, we narrow down the solutions to the set of all convex combinations of the two values, or to each of the two values.

On axiomatic characterizations of three pairs of covering based approximation operators

2010 ◽  
Vol 180 (2) ◽  
pp. 274-287 ◽  
Author(s):  
Yan-Lan Zhang ◽  
Jinjin Li ◽  
Wei-Zhi Wu
Keyword(s):  
Axiomatic Characterizations ◽  
Approximation Operators

scholarly journals Belief base rationalization for propositional merging

2018 ◽  
Vol 28 (7) ◽  
pp. 1601-1634 ◽  
Author(s):  
Nicolas Schwind ◽  
Sébastien Konieczny ◽  
Pierre Marquis
Keyword(s):  
Belief Base
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