Fitting Laplacian Regularized Stratified Gaussian Models
- URL: http://arxiv.org/abs/2005.01752v2
- Date: Fri, 22 May 2020 16:22:53 GMT
- Title: Fitting Laplacian Regularized Stratified Gaussian Models
- Authors: Jonathan Tuck, Stephen Boyd
- Abstract summary: We consider the problem of jointly estimating multiple related zero-mean Gaussian distributions from data.
We propose a distributed method that scales to large problems, and illustrate the efficacy of the method with examples in finance, radar signal processing, and weather forecasting.
- Score: 0.0
- License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
- Abstract: We consider the problem of jointly estimating multiple related zero-mean
Gaussian distributions from data. We propose to jointly estimate these
covariance matrices using Laplacian regularized stratified model fitting, which
includes loss and regularization terms for each covariance matrix, and also a
term that encourages the different covariances matrices to be close. This
method `borrows strength' from the neighboring covariances, to improve its
estimate. With well chosen hyper-parameters, such models can perform very well,
especially in the low data regime. We propose a distributed method that scales
to large problems, and illustrate the efficacy of the method with examples in
finance, radar signal processing, and weather forecasting.
Related papers
- Improving Probabilistic Diffusion Models With Optimal Covariance Matching [27.2761325416843]
We introduce a novel method for learning the diagonal covariances.
We show how our method can substantially enhance the sampling efficiency, recall rate and likelihood of both diffusion models and latent diffusion models.
arXiv Detail & Related papers (2024-06-16T05:47:12Z) - Collaborative Heterogeneous Causal Inference Beyond Meta-analysis [68.4474531911361]
We propose a collaborative inverse propensity score estimator for causal inference with heterogeneous data.
Our method shows significant improvements over the methods based on meta-analysis when heterogeneity increases.
arXiv Detail & Related papers (2024-04-24T09:04:36Z) - Distributed Markov Chain Monte Carlo Sampling based on the Alternating
Direction Method of Multipliers [143.6249073384419]
In this paper, we propose a distributed sampling scheme based on the alternating direction method of multipliers.
We provide both theoretical guarantees of our algorithm's convergence and experimental evidence of its superiority to the state-of-the-art.
In simulation, we deploy our algorithm on linear and logistic regression tasks and illustrate its fast convergence compared to existing gradient-based methods.
arXiv Detail & Related papers (2024-01-29T02:08:40Z) - Learning Graphical Factor Models with Riemannian Optimization [70.13748170371889]
This paper proposes a flexible algorithmic framework for graph learning under low-rank structural constraints.
The problem is expressed as penalized maximum likelihood estimation of an elliptical distribution.
We leverage geometries of positive definite matrices and positive semi-definite matrices of fixed rank that are well suited to elliptical models.
arXiv Detail & Related papers (2022-10-21T13:19:45Z) - Equivariance Discovery by Learned Parameter-Sharing [153.41877129746223]
We study how to discover interpretable equivariances from data.
Specifically, we formulate this discovery process as an optimization problem over a model's parameter-sharing schemes.
Also, we theoretically analyze the method for Gaussian data and provide a bound on the mean squared gap between the studied discovery scheme and the oracle scheme.
arXiv Detail & Related papers (2022-04-07T17:59:19Z) - A Robust and Flexible EM Algorithm for Mixtures of Elliptical
Distributions with Missing Data [71.9573352891936]
This paper tackles the problem of missing data imputation for noisy and non-Gaussian data.
A new EM algorithm is investigated for mixtures of elliptical distributions with the property of handling potential missing data.
Experimental results on synthetic data demonstrate that the proposed algorithm is robust to outliers and can be used with non-Gaussian data.
arXiv Detail & Related papers (2022-01-28T10:01:37Z) - Estimating Gaussian Copulas with Missing Data [0.0]
We show how to circumvent a priori assumptions on the marginals with semiparametric modelling.
The joint distribution learned through this algorithm is considerably closer to the underlying distribution than existing methods.
arXiv Detail & Related papers (2022-01-14T17:20:44Z) - A similarity-based Bayesian mixture-of-experts model [0.5156484100374058]
We present a new non-parametric mixture-of-experts model for multivariate regression problems.
Using a conditionally specified model, predictions for out-of-sample inputs are based on similarities to each observed data point.
Posterior inference is performed on the parameters of the mixture as well as the distance metric.
arXiv Detail & Related papers (2020-12-03T18:08:30Z) - Accounting for Unobserved Confounding in Domain Generalization [107.0464488046289]
This paper investigates the problem of learning robust, generalizable prediction models from a combination of datasets.
Part of the challenge of learning robust models lies in the influence of unobserved confounders.
We demonstrate the empirical performance of our approach on healthcare data from different modalities.
arXiv Detail & Related papers (2020-07-21T08:18:06Z) - Sparse Cholesky covariance parametrization for recovering latent
structure in ordered data [1.5349431582672617]
We focus on arbitrary zero patterns in the Cholesky factor of a covariance matrix.
For the ordered scenario, we propose a novel estimation method that is based on matrix loss penalization.
We give guidelines, based on the empirical results, about which of the methods analysed is more appropriate for each setting.
arXiv Detail & Related papers (2020-06-02T08:35:00Z) - Covariance Estimation for Matrix-valued Data [9.739753590548796]
We propose a class of distribution-free regularized covariance estimation methods for high-dimensional matrix data.
We formulate a unified framework for estimating bandable covariance, and introduce an efficient algorithm based on rank one unconstrained Kronecker product approximation.
We demonstrate the superior finite-sample performance of our methods using simulations and real applications from a gridded temperature anomalies dataset and a S&P 500 stock data analysis.
arXiv Detail & Related papers (2020-04-11T02:15:26Z)
This list is automatically generated from the titles and abstracts of the papers in this site.
This site does not guarantee the quality of this site (including all information) and is not responsible for any consequences.