278,796 research outputs found
Metrics for Measuring Data Quality - Foundations for an Economic Oriented Management of Data Quality
The article develops metrics for an economic oriented management of data quality. Two data quality dimensions are focussed: consistency and timeliness. For deriving adequate metrics several requirements are stated (e. g. normalisation, cardinality, adaptivity, interpretability). Then the authors discuss existing approaches for measuring data quality and illustrate their weaknesses. Based upon these considerations, new metrics are developed for the data quality dimensions consistency and timeliness. These metrics are applied in practice and the results are illustrated in the case of a major German mobile services provider
The New Quantum Logic
It is shown how all the major conceptual difficulties of standard (textbook)
quantum mechanics, including the two measurement problems and the (supposed)
nonlocality that conflicts with special relativity, are resolved in the
consistent or decoherent histories interpretation of quantum mechanics by using
a modified form of quantum logic to discuss quantum properties (subspaces of
the quantum Hilbert space), and treating quantum time development as a
stochastic process. The histories approach in turn gives rise to some
conceptual difficulties, in particular the correct choice of a framework
(probabilistic sample space) or family of histories, and these are discussed.
The central issue is that the principle of unicity, the idea that there is a
unique single true description of the world, is incompatible with our current
understanding of quantum mechanics.Comment: Minor changes and corrections to bring into conformity with published
versio
A Consistent Quantum Ontology
The (consistent or decoherent) histories interpretation provides a consistent
realistic ontology for quantum mechanics, based on two main ideas. First, a
logic (system of reasoning) is employed which is compatible with the
Hilbert-space structure of quantum mechanics as understood by von Neumann:
quantum properties and their negations correspond to subspaces and their
orthogonal complements. It employs a special (single framework) syntactical
rule to construct meaningful quantum expressions, quite different from the
quantum logic of Birkhoff and von Neumann. Second, quantum time development is
treated as an inherently stochastic process under all circumstances, not just
when measurements take place. The time-dependent Schr\"odinger equation
provides probabilities, not a deterministic time development of the world. The
resulting interpretive framework has no measurement problem and can be used to
analyze in quantum terms what is going on before, after, and during physical
preparation and measurement processes. In particular, appropriate measurements
can reveal quantum properties possessed by the measured system before the
measurement took place. There are no mysterious superluminal influences:
quantum systems satisfy an appropriate form of Einstein locality. This ontology
provides a satisfactory foundation for quantum information theory, since it
supplies definite answers as to what the information is about. The formalism of
classical (Shannon) information theory applies without change in suitable
quantum contexts, and this suggests the way in which quantum information theory
extends beyond its classical counterpart.Comment: Very minor revisions to previous versio
Decoherence, the measurement problem, and interpretations of quantum mechanics
Environment-induced decoherence and superselection have been a subject of
intensive research over the past two decades, yet their implications for the
foundational problems of quantum mechanics, most notably the quantum
measurement problem, have remained a matter of great controversy. This paper is
intended to clarify key features of the decoherence program, including its more
recent results, and to investigate their application and consequences in the
context of the main interpretive approaches of quantum mechanics.Comment: 41 pages. Final published versio
Enhancing Decision Tree based Interpretation of Deep Neural Networks through L1-Orthogonal Regularization
One obstacle that so far prevents the introduction of machine learning models
primarily in critical areas is the lack of explainability. In this work, a
practicable approach of gaining explainability of deep artificial neural
networks (NN) using an interpretable surrogate model based on decision trees is
presented. Simply fitting a decision tree to a trained NN usually leads to
unsatisfactory results in terms of accuracy and fidelity. Using L1-orthogonal
regularization during training, however, preserves the accuracy of the NN,
while it can be closely approximated by small decision trees. Tests with
different data sets confirm that L1-orthogonal regularization yields models of
lower complexity and at the same time higher fidelity compared to other
regularizers.Comment: 8 pages, 18th IEEE International Conference on Machine Learning and
Applications (ICMLA) 201
EPR, Bell, and Quantum Locality
Maudlin has claimed that no local theory can reproduce the predictions of
standard quantum mechanics that violate Bell's inequality for Bohm's version
(two spin-half particles in a singlet state) of the Einstein-Podolsky-Rosen
problem. It is argued that, on the contrary, standard quantum mechanics itself
is a counterexample to Maudlin's claim, because it is local in the appropriate
sense (measurements at one place do not influence what occurs elsewhere there)
when formulated using consistent principles in place of the inconsistent
appeals to "measurement" found in current textbooks. This argument sheds light
on the claim of Blaylock that counterfactual definiteness is an essential
ingredient in derivations of Bell's inequality.Comment: Minor revisions to previous versio
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