681 research outputs found
A First-Order Logic for Reasoning about Knowledge and Probability
We present a first-order probabilistic epistemic logic, which allows
combining operators of knowledge and probability within a group of possibly
infinitely many agents. The proposed framework is the first order extension of
the logic of Fagin and Halpern from (J.ACM 41:340-367,1994). We define its
syntax and semantics, and prove the strong completeness property of the
corresponding axiomatic system.Comment: 29. pages. This paper is revised and extended version of the
conference paper presented at the Thirteenth European Conference on Symbolic
and Quantitative Approaches to Reasoning with Uncertainty (ECSQARU 2015), in
which we introduced the propositional variant of the logic presented here,
using a similar axiomatization techniqu
Automatic White-Box Testing of First-Order Logic Ontologies
Formal ontologies are axiomatizations in a logic-based formalism. The
development of formal ontologies, and their important role in the Semantic Web
area, is generating considerable research on the use of automated reasoning
techniques and tools that help in ontology engineering. One of the main aims is
to refine and to improve axiomatizations for enabling automated reasoning tools
to efficiently infer reliable information. Defects in the axiomatization can
not only cause wrong inferences, but can also hinder the inference of expected
information, either by increasing the computational cost of, or even
preventing, the inference. In this paper, we introduce a novel, fully automatic
white-box testing framework for first-order logic ontologies. Our methodology
is based on the detection of inference-based redundancies in the given
axiomatization. The application of the proposed testing method is fully
automatic since a) the automated generation of tests is guided only by the
syntax of axioms and b) the evaluation of tests is performed by automated
theorem provers. Our proposal enables the detection of defects and serves to
certify the grade of suitability --for reasoning purposes-- of every axiom. We
formally define the set of tests that are generated from any axiom and prove
that every test is logically related to redundancies in the axiom from which
the test has been generated. We have implemented our method and used this
implementation to automatically detect several non-trivial defects that were
hidden in various first-order logic ontologies. Throughout the paper we provide
illustrative examples of these defects, explain how they were found, and how
each proof --given by an automated theorem-prover-- provides useful hints on
the nature of each defect. Additionally, by correcting all the detected
defects, we have obtained an improved version of one of the tested ontologies:
Adimen-SUMO.Comment: 38 pages, 5 table
Economic Theory in the Mathematical Mode
Lecture to the memory of Alfred Nobel, December 8, 1983general equilibrium;
A THEORY OF RATIONAL CHOICE UNDER COMPLETE IGNORANCE
This paper contributes to a theory of rational choice under uncertainty for decision-makers whose preferences are exhaustively described by partial orders representing ""limited information."" Specifically, we consider the limiting case of ""Complete Ignorance"" decision problems characterized by maximally incomplete preferences and important primarily as reduced forms of general decision problems under uncertainty. ""Rationality"" is conceptualized in terms of a ""Principle of Preference-Basedness,"" according to which rational choice should be isomorphic to asserted preference. The main result characterizes axiomatically a new choice-rule called ""Simultaneous Expected Utility Maximization"" which in particular satisfies a choice-functional independence and a context-dependent choice-consistency condition; it can be interpreted as the fair agreement in a bargaining game (Kalai-Smorodinsky solution) whose players correspond to the different possible states (respectively extermal priors in the general case).
Related families-based attribute reduction of dynamic covering information systems with variations of object sets
In practice, there are many dynamic covering decision information systems,
and knowledge reduction of dynamic covering decision information systems is a
significant challenge of covering-based rough sets. In this paper, we first
study mechanisms of constructing attribute reducts for consistent covering
decision information systems when adding objects using related families. We
also employ examples to illustrate how to construct attribute reducts of
consistent covering decision information systems when adding objects. Then we
investigate mechanisms of constructing attribute reducts for consistent
covering decision information systems when deleting objects using related
families. We also employ examples to illustrate how to construct attribute
reducts of consistent covering decision information systems when deleting
objects. Finally, the experimental results illustrates that the related
family-based methods are effective to perform attribute reduction of dynamic
covering decision information systems when object sets are varying with time.Comment: arXiv admin note: substantial text overlap with arXiv:1711.0732
A Novel Approach for Mining Similarity Profiled Temporal Association Patterns
The problem of frequent pattern mining from non-temporal databases is studied
extensively by various researchers working in areas of data mining, temporal
databases and information retrieval. However, Conventional frequent pattern
algorithms are not suitable to find similar temporal association patterns from
temporal databases. A Temporal database is a database which can store past,
present and future information. The objective of this research is to come up
with a novel approach so as to find similar temporal association patterns w.r.t
user specified threshold and a given reference support time sequence using
concept of Venn diagrams. For this, we maintain two types of supports called
positive support and negative support values to find similar temporal
association patterns of user interest. The main advantage of our method is
that, it performs only a single scan of temporal database to find temporal
association patterns similar to specified reference support sequence. This
single database scan approach hence eliminates the huge overhead incurred when
the database is scanned multiple times. The present approach also eliminates
the need to compute and maintain true support values of all the subsets of
temporal patterns of previous stages when computing temporal patterns of next
stage.Comment: Technical Journal of the Faculty of Engineering, 14 page
The many Shapley values for model explanation
The Shapley value has become a popular method to attribute the prediction of
a machine-learning model on an input to its base features. The use of the
Shapley value is justified by citing [16] showing that it is the \emph{unique}
method that satisfies certain good properties (\emph{axioms}).
There are, however, a multiplicity of ways in which the Shapley value is
operationalized in the attribution problem. These differ in how they reference
the model, the training data, and the explanation context. These give very
different results, rendering the uniqueness result meaningless. Furthermore, we
find that previously proposed approaches can produce counterintuitive
attributions in theory and in practice---for instance, they can assign non-zero
attributions to features that are not even referenced by the model.
In this paper, we use the axiomatic approach to study the differences between
some of the many operationalizations of the Shapley value for attribution, and
propose a technique called Baseline Shapley (BShap) that is backed by a proper
uniqueness result. We also contrast BShap with Integrated Gradients, another
extension of Shapley value to the continuous setting.Comment: 9 page
Axiomatic foundations of nonrelativistic quantum mechanics: a realistic approach
A realistic axiomatic formulation of nonrelativistic quantum mechanics for a single microsystem with spin is presented, from which the most important theorems of the theory can be deduced. In comparison with previous formulations, the formal aspect has been improved by the use of certain mathematical theories, such as the theory of equipped spaces, and group theory. The standard formalism is naturally obtained from the latter, starting from a central primitive concept: the Galilei group
Distances between Data Sets Based on Summary Statistics
The concepts of similarity and distance are crucial in data mining. We
consider the problem of defining the distance between two data sets by
comparing summary statistics computed from the data sets. The initial
definition of our distance is based on geometrical notions of certain sets of
distributions. We show that this distance can be computed in cubic time and
that it has several intuitive properties. We also show that this distance is
the unique Mahalanobis distance satisfying certain assumptions. We also
demonstrate that if we are dealing with binary data sets, then the distance can
be represented naturally by certain parity functions, and that it can be
evaluated in linear time. Our empirical tests with real world data show that
the distance works well
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