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Related papers: Flexible Mixture Modeling on Constrained Spaces

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We propose models and algorithms for learning about random directions in two-dimensional simplex data, and apply our methods to the study of income level proportions and their changes over time in a geostatistical area. There are several…

Methodology · Statistics 2022-05-24 Rayleigh Lei , XuanLong Nguyen

We propose a method that performs anomaly detection and localisation within heterogeneous data using a pairwise undirected mixed graphical model. The data are a mixture of categorical and quantitative variables, and the model is learned…

Machine Learning · Statistics 2016-07-21 Romain Laby , François Roueff , Alexandre Gramfort

Binomial data with unknown sizes often appear in biological and medical sciences and are usually overdispersed. All previous methods used parametric models and only considered overdispersion due to the variation of sizes. The proposed…

Statistics Theory · Mathematics 2007-06-13 Wei Zhang

In recent work we have shown how an accurate reduced model can be utilized to perform mesh refinement in random space. That work relied on the explicit knowledge of an accurate reduced model which is used to monitor the transfer of activity…

Numerical Analysis · Mathematics 2016-09-21 Jing Li , Panos Stinis

While existing mathematical descriptions can accurately account for phenomena at microscopic scales (e.g. molecular dynamics), these are often high-dimensional, stochastic and their applicability over macroscopic time scales of physical…

Machine Learning · Statistics 2016-09-08 P. S. Koutsourelakis , Elias Bilionis

It is now practically the norm for data to be very high dimensional in areas such as genetics, machine vision, image analysis and many others. When analyzing such data, parametric models are often too inflexible while nonparametric…

Methodology · Statistics 2011-05-31 Abhishek Bhattacharya , Garritt Page , David Dunson

Model-based clustering of moderate or large dimensional data is notoriously difficult. We propose a model for simultaneous dimensionality reduction and clustering by assuming a mixture model for a set of latent scores, which are then linked…

Methodology · Statistics 2024-06-04 Lorenzo Ghilotti , Mario Beraha , Alessandra Guglielmi

Mixture models whose components have skewed hypercube contours are developed via a generalization of the multivariate shifted asymmetric Laplace density. Specifically, we develop mixtures of multiple scaled shifted asymmetric Laplace…

Methodology · Statistics 2023-03-28 Brian C. Franczak , Cristina Tortora , Ryan P. Browne , Paul D. McNicholas

Fully describing the entire data set is essential in multivariate risk assessment, since moderate levels of one variable can influence another, potentially leading it to be extreme. Additionally, modelling both non-extreme and extreme…

Methodology · Statistics 2025-03-11 Lídia M. André , Jonathan A. Tawn

We develop Bayesian nonparametric models for spatially indexed data of mixed type. Our work is motivated by challenges that occur in environmental epidemiology, where the usual presence of several confounding variables that exhibit complex…

Methodology · Statistics 2014-10-17 Georgios Papageorgiou , Sylvia Richardson , Nicky Best

A challenge arising from the local Bayesian assimilation of data in an atmospheric flow simulation is the imbalances it may introduce. Acoustic fast-mode imbalances of the order of the slower dynamics can be negated by employing a blended…

Numerical Analysis · Mathematics 2024-03-11 Ray Chew , Tommaso Benacchio , Gottfried Hastermann , Rupert Klein

Astronomical data often suffer from noise and incompleteness. We extend the common mixtures-of-Gaussians density estimation approach to account for situations with a known sample incompleteness by simultaneous imputation from the current…

Instrumentation and Methods for Astrophysics · Physics 2020-09-17 Peter Melchior , Andy D. Goulding

This work presents a model reduction approach for problems with coherent structures that propagate over time such as convection-dominated flows and wave-type phenomena. Traditional model reduction methods have difficulties with these…

Numerical Analysis · Mathematics 2020-06-16 Benjamin Peherstorfer

Sampling from unnormalized densities using diffusion models has emerged as a powerful paradigm. However, while recent approaches that use least-squares `matching' objectives have improved scalability, they often necessitate significant…

Machine Learning · Computer Science 2026-03-03 Denis Blessing , Lorenz Richter , Julius Berner , Egor Malitskiy , Gerhard Neumann

We introduce a learning-based algorithm to obtain a measurement matrix for compressive sensing related recovery problems. The focus lies on matrices with a constant modulus constraint which typically represent a network of analog phase…

Signal Processing · Electrical Eng. & Systems 2021-10-15 Michael Koller , Wolfgang Utschick

The Dirichlet process mixture model and more general mixtures based on discrete random probability measures have been shown to be flexible and accurate models for density estimation and clustering. The goal of this paper is to illustrate…

Methodology · Statistics 2013-10-02 Ernesto Barrios , Antonio Lijoi , Luis E. Nieto-Barajas , Igor Prünster

Rapid progress in representation learning has led to a proliferation of embedding models, and to associated challenges of model selection and practical application. It is non-trivial to assess a model's generalizability to new, candidate…

Machine Learning · Computer Science 2022-02-18 Leo Betthauser , Urszula Chajewska , Maurice Diesendruck , Rohith Pesala

We explore the probabilistic foundations of shared control in complex dynamic environments. In order to do this, we formulate shared control as a random process and describe the joint distribution that governs its behavior. For…

Robotics · Computer Science 2015-08-10 Pete Trautman

Convergence analysis of Markov chain Monte Carlo methods in high-dimensional statistical applications is increasingly recognized. In this paper, we develop general mixing time bounds for Metropolis-Hastings algorithms on discrete spaces by…

Computation · Statistics 2025-07-29 Hyunwoong Chang , Quan Zhou

Survival analysis is a widely-used technique for analyzing time-to-event data in the presence of censoring. In recent years, numerous survival analysis methods have emerged which scale to large datasets and relax traditional assumptions…

Machine Learning · Computer Science 2023-11-06 Mert Ketenci , Shreyas Bhave , Noémie Elhadad , Adler Perotte