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Related papers: Covariance Prediction via Convex Optimization

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This paper proves, in very general settings, that convex risk minimization is a procedure to select a unique conditional probability model determined by the classification problem. Unlike most previous work, we give results that are general…

Machine Learning · Computer Science 2015-06-16 Matus Telgarsky , Miroslav Dudík , Robert Schapire

Consider the problem of estimating the mean of a Gaussian random vector when the mean vector is assumed to be in a given convex set. The most natural solution is to take the Euclidean projection of the data vector on to this convex set; in…

Statistics Theory · Mathematics 2014-11-21 Sourav Chatterjee

Covariance selection seeks to estimate a covariance matrix by maximum likelihood while restricting the number of nonzero inverse covariance matrix coefficients. A single penalty parameter usually controls the tradeoff between log likelihood…

Optimization and Control · Mathematics 2010-10-12 Vijay Krishnamurthy , Alexandre d'Aspremont

We study Bayesian inference methods for solving linear inverse problems, focusing on hierarchical formulations where the prior or the likelihood function depend on unspecified hyperparameters. In practice, these hyperparameters are often…

Numerical Analysis · Mathematics 2018-08-01 Qingping Zhou , Wenqing Liu , Jinglai Li , Youssef M. Marzouk

In this paper we propose a general methodology, based on multiple testing, for testing that the mean of a Gaussian vector in R^n belongs to a convex set. We show that the test achieves its nominal level, and characterize a class of vectors…

Statistics Theory · Mathematics 2007-06-13 Yannick Baraud , Sylvie Huet , Beatrice Laurent

Variable selection for Gaussian process models is often done using automatic relevance determination, which uses the inverse length-scale parameter of each input variable as a proxy for variable relevance. This implicitly determined…

Methodology · Statistics 2019-04-24 Topi Paananen , Juho Piironen , Michael Riis Andersen , Aki Vehtari

Sparse Gaussian graphical models characterize sparse dependence relationships between random variables in a network. To estimate multiple related Gaussian graphical models on the same set of variables, we formulate a hierarchical model,…

Methodology · Statistics 2014-06-10 Yuancheng Zhu , Rina Foygel Barber

When inferring parameters from a Gaussian-distributed data set by computing a likelihood, a covariance matrix is needed that describes the data errors and their correlations. If the covariance matrix is not known a priori, it may be…

Cosmology and Nongalactic Astrophysics · Physics 2016-01-27 Elena Sellentin , Alan F. Heavens

Latent Gaussian models (LGMs) are widely used in statistics and machine learning. Bayesian inference in non-conjugate LGMs is difficult due to intractable integrals involving the Gaussian prior and non-conjugate likelihoods. Algorithms…

Machine Learning · Statistics 2013-06-06 Mohammad Emtiyaz Khan , Aleksandr Y. Aravkin , Michael P. Friedlander , Matthias Seeger

Sparse inverse covariance selection is a fundamental problem for analyzing dependencies in high dimensional data. However, such a problem is difficult to solve since it is NP-hard. Existing solutions are primarily based on convex…

Numerical Analysis · Computer Science 2018-04-05 Ganzhao Yuan , Haoxian Tan , Wei-Shi Zheng

We propose a computationally efficient estimator, formulated as a convex program, for a broad class of non-linear regression problems that involve difference of convex (DC) non-linearities. The proposed method can be viewed as a significant…

Machine Learning · Statistics 2019-04-01 Sohail Bahmani

Given noisy data, function estimation is considered when the unknown function is known apriori to consist of a small number of regions where the function is either convex or concave. When the regions are known apriori, the estimate is…

Methodology · Statistics 2020-02-18 Kurt S. Riedel

Regularization plays a key role in a variety of optimization formulations of inverse problems. A recurring theme in regularization approaches is the selection of regularization parameters, and their effect on the solution and on the optimal…

Optimization and Control · Mathematics 2018-08-23 Aleksandr Y. Aravkin , James V. Burke , Michael P. Friedlander

Devising efficient algorithms that track the optimizers of continuously varying convex optimization problems is key in many applications. A possible strategy is to sample the time-varying problem at constant rate and solve the resulting…

Optimization and Control · Mathematics 2017-11-28 Andrea Simonetto

Finding a point in the intersection of a collection of closed convex sets, that is the convex feasibility problem, represents the main modeling strategy for many computational problems. In this paper we analyze new stochastic reformulations…

Optimization and Control · Mathematics 2018-01-16 Ion Necoara , Peter Richtarik , Andrei Patrascu

A number of results related to statistical classification on convex sets are presented. In particular, the focus is on the case where some of the covariates in the data and observation being classified can be missing. The form of the…

Statistics Theory · Mathematics 2018-05-02 Levon Demirdjian , Majid Mojirsheibani

Covariance matrix estimation arises in multivariate problems including multivariate normal sampling models and regression models where random effects are jointly modeled, e.g. random-intercept, random-slope models. A Bayesian analysis of…

Methodology · Statistics 2016-07-14 Ignacio Alvarez , Jarad Niemi , Matt Simpson

In this paper, we study randomized and cyclic coordinate descent for convex unconstrained optimization problems. We improve the known convergence rates in some cases by using the numerical semidefinite programming performance estimation…

Optimization and Control · Mathematics 2022-12-26 Hadi Abbaszadehpeivasti , Etienne de Klerk , Moslem Zamani

We consider the problem of forecasting multiple values of the future of a vector time series, using some past values. This problem, and related ones such as one-step-ahead prediction, have a very long history, and there are a number of…

Machine Learning · Statistics 2021-02-01 Shane Barratt , Yining Dong , Stephen Boyd

We introduce a new sparse estimator of the covariance matrix for high-dimensional models in which the variables have a known ordering. Our estimator, which is the solution to a convex optimization problem, is equivalently expressed as an…

Statistics Theory · Mathematics 2014-05-27 Jacob Bien , Florentina Bunea , Luo Xiao