Non-linear Latent Variable Models for Inference and Learning from Non-Gaussian Data
Title | Non-linear Latent Variable Models for Inference and Learning from Non-Gaussian Data PDF eBook |
Author | Hamid Mousavi |
Publisher | |
Pages | 0 |
Release | 2022 |
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We present a family of probabilistic generative models that encompasses a variety of probability distributions (including Gaussian, Gamma, Beta, Poisson and many more) from the exponential family. In addition, we investigate a point-wise maximum function and introduce a novel non-linear superposition for coupling the latents and observables using two matrices (if the considered noise distribution has two parameters): One to model the component means and another for component variances. We further exploit the Expectation Maximization (EM) algorithm and show that the presented link function allows for the derivation of a very general and concise set of parameter update equations. Concretely, we derive a set of updates that have the same functional form for all regular distributions of the exponential family. Our results then provide directly applicable learning equations for commonly as well as for unusually distributed data. Finally, to assess the reliability of our theoretical findings, we consider different applications of the proposed generative models and investigate a variety of complex datasets including both synthetic and real data.
Enabling Feature-level Interpretability in Non-linear Latent Variable Models
Title | Enabling Feature-level Interpretability in Non-linear Latent Variable Models PDF eBook |
Author | Kaspar Märtens |
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Pages | |
Release | 2019 |
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Non-linear Latent Factor Models for Revealing Structure in High-dimensional Data
Title | Non-linear Latent Factor Models for Revealing Structure in High-dimensional Data PDF eBook |
Author | Roland Memisevic |
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Information Theory, Inference and Learning Algorithms
Title | Information Theory, Inference and Learning Algorithms PDF eBook |
Author | David J. C. MacKay |
Publisher | Cambridge University Press |
Pages | 694 |
Release | 2003-09-25 |
Genre | Computers |
ISBN | 9780521642989 |
Information theory and inference, taught together in this exciting textbook, lie at the heart of many important areas of modern technology - communication, signal processing, data mining, machine learning, pattern recognition, computational neuroscience, bioinformatics and cryptography. The book introduces theory in tandem with applications. Information theory is taught alongside practical communication systems such as arithmetic coding for data compression and sparse-graph codes for error-correction. Inference techniques, including message-passing algorithms, Monte Carlo methods and variational approximations, are developed alongside applications to clustering, convolutional codes, independent component analysis, and neural networks. Uniquely, the book covers state-of-the-art error-correcting codes, including low-density-parity-check codes, turbo codes, and digital fountain codes - the twenty-first-century standards for satellite communications, disk drives, and data broadcast. Richly illustrated, filled with worked examples and over 400 exercises, some with detailed solutions, the book is ideal for self-learning, and for undergraduate or graduate courses. It also provides an unparalleled entry point for professionals in areas as diverse as computational biology, financial engineering and machine learning.
Handbook of Graphical Models
Title | Handbook of Graphical Models PDF eBook |
Author | Marloes Maathuis |
Publisher | CRC Press |
Pages | 612 |
Release | 2018-11-12 |
Genre | Mathematics |
ISBN | 0429874235 |
A graphical model is a statistical model that is represented by a graph. The factorization properties underlying graphical models facilitate tractable computation with multivariate distributions, making the models a valuable tool with a plethora of applications. Furthermore, directed graphical models allow intuitive causal interpretations and have become a cornerstone for causal inference. While there exist a number of excellent books on graphical models, the field has grown so much that individual authors can hardly cover its entire scope. Moreover, the field is interdisciplinary by nature. Through chapters by leading researchers from different areas, this handbook provides a broad and accessible overview of the state of the art. Key features: * Contributions by leading researchers from a range of disciplines * Structured in five parts, covering foundations, computational aspects, statistical inference, causal inference, and applications * Balanced coverage of concepts, theory, methods, examples, and applications * Chapters can be read mostly independently, while cross-references highlight connections The handbook is targeted at a wide audience, including graduate students, applied researchers, and experts in graphical models.
Practical Algorithms for Latent Variable Models
Title | Practical Algorithms for Latent Variable Models PDF eBook |
Author | Gregory W. Gundersen |
Publisher | |
Pages | 0 |
Release | 2021 |
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Latent variables allow researchers and engineers to encode assumptions into their statistical models. A latent variable might, for example, represent an unobserved covariate, measurement error, or a missing class label. Inference is challenging because one must account for the conditional dependence structure induced by these variables, and marginalization is often intractable. In this thesis, I present several practical algorithms for inferring latent structure in probabilistic models used in computational biology, neuroscience, and time-series analysis.First, I present a multi-view framework that combines neural networks and probabilistic canonical correlation analysis to estimate shared and view-specific latent structure of paired samples of histological images and gene expression levels. The model is trained end-to-end to estimate all parameters simultaneously, and we show that the latent variables capture interpretable structure, such as tissue-specific and morphological variation. Next, I present a family of nonlinear dimension-reduction models that use random features to support non-Gaussian data likelihoods. By approximating a nonlinear relationship between the latent variables and observations with a function that is linear with respect to random features, we induce closed-form gradients of the posterior distribution with respect to the latent variables. This allows for gradient-based nonlinear dimension-reduction models for a variety of data likelihoods. Finally, I discuss lowering the computational cost of online Bayesian filtering of time series with abrupt changes in structure, called changepoints. We consider settings in which a time series has multiple data sources, each with an associated cost. We trade the cost of a data source against the quality or fidelity of that source and how its fidelity affects the estimation of changepoints. Our framework makes cost-sensitive decisions about which data source to use based on minimizing the information entropy of the posterior distribution over changepoints.
Backward Simulation Methods for Monte Carlo Statistical Inference
Title | Backward Simulation Methods for Monte Carlo Statistical Inference PDF eBook |
Author | Fredrik Lindsten |
Publisher | |
Pages | 145 |
Release | 2013 |
Genre | Digital computer simulation |
ISBN | 9781601986993 |
Backward Simulation Methods for Monte Carlo Statistical Inference presents and discusses various backward simulation methods for Monte Carlo statistical inference. The focus is on SMC-based backward simulators, which are useful for inference in analytically intractable models, such as nonlinear and/or non-Gaussian SSMs, but also in more general latent variable models.