The combined use of graphicalmodels and probabilistic techniques has been shown to be highly effective in applications involving the uncertain data from industrial environments. In addition, industrial data analysis ...
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ISBN:
(纸本)9781509060146
The combined use of graphicalmodels and probabilistic techniques has been shown to be highly effective in applications involving the uncertain data from industrial environments. In addition, industrial data analysis has been a necessary and interesting approach for systems in industry 4.0. The present paper proposes a probabilisticgraphical model to infer the probability of the path presenting a packet delivery ratio (PDR) above a threshold. The technique used was Bayesian Network, however selection and discretization techniques were applied prior to data processing. These data were collected froma real WirelessHART network. The results show the applicability of the probabilistics method to real problems of industrial network.
Structure learning methods for covariance and concentration graphs are often validated on synthetic models, usually obtained by randomly generating: (i) an undirected graph, and (ii) a compatible symmetric positive de...
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Structure learning methods for covariance and concentration graphs are often validated on synthetic models, usually obtained by randomly generating: (i) an undirected graph, and (ii) a compatible symmetric positive definite (SPD) matrix. In order to ensure positive definiteness in (ii), a dominant diagonal is usually imposed. In this work we investigate different methods to generate random symmetric positive definite matrices with undirected graphical constraints. We show that if the graph is chordal it is possible to sample uniformly from the set of correlation matrices compatible with the graph, while for general undirected graphs we rely on a partial orthogonalization method. (C) 2020 Elsevier Inc. All rights reserved.
In this paper, we present Prometheus, a graph partitioning based algorithm that creates multiple variable decompositions efficiently for learning Sum-Product Network structures across both continuous and discrete doma...
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In this paper, we present Prometheus, a graph partitioning based algorithm that creates multiple variable decompositions efficiently for learning Sum-Product Network structures across both continuous and discrete domains. Prometheus proceeds by creating multiple candidate decompositions that are represented compactly with an acyclic directed graph in which common parts of different decompositions are shared. It eliminates the correlation threshold hyperparameter often used in other structure learning techniques, allowing Prometheus to learn structures that are robust in low data regimes. Prometheus outperforms other structure learning techniques in 30 discrete and continuous domains. We also extend Prometheus to exploit sparsity in correlations between features in order to obtain an efficient sub-quadratic algorithm (w.r.t. the number of features) that scales better to high dimensional datasets. (C) 2020 The Authors. Published by Elsevier Inc.
Forecasting represents a very important task for control and decision making in many fields. Forecasting the dollar price is important for global companies to plan their investments. Forecasting the wind speed for a d...
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ISBN:
(纸本)9781509001910
Forecasting represents a very important task for control and decision making in many fields. Forecasting the dollar price is important for global companies to plan their investments. Forecasting the wind speed for a day-ahead horizon allows dispatching clean energy efficiently. One technique developed by the artificial intelligence community that has proved to be efficient for forecasting is the probabilisticgraphicalmodels approach. In order to obtain accurate models for forecasting, there exist different assumptions that might be made. This paper presents these assumptions and the results of different experiments conducted to define the characteristics of good probabilisticgraphicalmodels. A performance comparison of several graphicalmodels is also presented. The experiments were executed to forecast wind velocity and hence, wind power in wind farms.
The ever increasing use of intelligent multi-agent systems poses increasing demands upon them. One of these is the ability to reason consistently under uncertainty. This, in turn, is the dominant characteristic of pro...
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ISBN:
(纸本)0780392868
The ever increasing use of intelligent multi-agent systems poses increasing demands upon them. One of these is the ability to reason consistently under uncertainty. This, in turn, is the dominant characteristic of probabilistic learning in graphicalmodels which, however, lack a natural decentralised formulation. The ideal would, therefore, be a unifying framework which is able to combine the strengths of both multi-agent and probabilistic inference In this paper we present a unified interpretation of the inference mechanisms in games and graphicalmodels. In particular, we view fictitious play as a method of optimising the Kullback-Leibler distance between current mixed strategies and optimal mixed strategies at Nash equilibrium. In reverse, probabilistic inference in the variational mean-field framework can be viewed as fictitious game play to learn the best strategies which explain a probabilisticgraphical model.
In this paper a modular approach to single-microphone source separation is proposed. A probabilistic model for mixtures of observations is constructed, where the independent underlying source signals are described by ...
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In this paper a modular approach to single-microphone source separation is proposed. A probabilistic model for mixtures of observations is constructed, where the independent underlying source signals are described by non-linear autoregressive models. Source separation in this model is achieved by performing online probabilistic inference through an efficient message passing procedure. For retaining tractability with the non-linear autoregressive models, three different approximation methods are described. A set of experiments shows the effectiveness of the proposed source separation approach. The source separation performance of the different approximation methods is quantified through a set of verification experiments. Our approach is validated in a speech denoising task.
graphicalmodels and general purpose inference algorithms are powerful tools for moving from imperative towards declarative specification of machine learning problems. Although graphicalmodels define the principle in...
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ISBN:
(纸本)9781479925049
graphicalmodels and general purpose inference algorithms are powerful tools for moving from imperative towards declarative specification of machine learning problems. Although graphicalmodels define the principle information necessary to adapt inference algorithms to specific probabilisticmodels, entirely model-driven development is not yet possible. However, generating executable code from graphicalmodels could have several advantages. It could reduce the skills necessary to implement probabilisticmodels and may speed up development processes. Both advantages address pressing industry needs. They come along with increased supply of data scientist labor, the demand of which cannot be fulfilled at the moment. To explore the opportunities of model-driven big data analytics, I review the main modeling languages used in machine learning as well as inference algorithms and corresponding software implementations. Gaps hampering direct code generation from graphicalmodels are identified and closed by proposing an initial conceptualization of a domain-specific modeling language.
InferPy is an open-source Python package for variational inference in probabilisticmodels containing neural networks. Other similar libraries are often difficult for non-expert users. InferPy provides a much more com...
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InferPy is an open-source Python package for variational inference in probabilisticmodels containing neural networks. Other similar libraries are often difficult for non-expert users. InferPy provides a much more compact and simple way to code such models, at the expense of slightly reducing expressibility and flexibility. The main objective of this package is to permit its use without having a strong theoretical background or thorough knowledge of the deep learning frameworks.
Several structural learning algorithms for staged tree models, an asymmetric extension of Bayesian networks, have been defined. However, they do not scale efficiently as the number of variables considered increases. H...
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Several structural learning algorithms for staged tree models, an asymmetric extension of Bayesian networks, have been defined. However, they do not scale efficiently as the number of variables considered increases. Here we introduce the first scalable structural learning algorithm for staged trees, which searches over a space of models where only a small number of dependencies can be imposed. A simulation study as well as a real-world application illustrate our routines and the practical use of such data-learned staged trees.
The problem of discovering a structure that fits a collection of vector data is of crucial importance for a variety of applications. Such problems can be framed as Laplacian constrained Gaussian graphical Model infere...
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The problem of discovering a structure that fits a collection of vector data is of crucial importance for a variety of applications. Such problems can be framed as Laplacian constrained Gaussian graphical Model inference. Existing algorithms rely on the assumption that all the available observations are drawn from the same Multivariate Gaussian distribution. However, in practice it is common to find scenarios where the datasets are contaminated with a certain number of outliers. The purpose of this work is to address that problem. We propose a robust method based on Trimmed Least Squares that copes with the presence of corrupted samples. We provide statistical guarantees on the estimation error and present results on both simulated data and real-world data.
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