English
Related papers

Related papers: A semiparametric scale-mixture regression model an…

200 papers

An important and yet difficult problem in fitting multivariate mixture models is determining the mixture complexity. We develop theory and a unified framework for finding the nonparametric maximum likelihood estimator of a multivariate…

Statistics Theory · Mathematics 2007-06-13 Ramani S. Pilla , Francesco Bartolucci , Bruce G. Lindsay

We present algorithms for nonparametric regression in settings where the data are obtained sequentially. While traditional estimators select bandwidths that depend upon the sample size, for sequential data the effective sample size is…

Methodology · Statistics 2012-07-03 Haijie Gu , John Lafferty

Nonparametric mixture models based on the Dirichlet process are an elegant alternative to finite models when the number of underlying components is unknown, but inference in such models can be slow. Existing attempts to parallelize…

Machine Learning · Statistics 2012-12-03 Sinead A. Williamson , Avinava Dubey , Eric P. Xing

Clustered competing risks data are commonly encountered in multicenter studies. The analysis of such data is often complicated due to informative cluster size, a situation where the outcomes under study are associated with the size of the…

Methodology · Statistics 2021-04-26 Wenxian Zhou , Giorgos Bakoyannis , Ying Zhang , Constantin T. Yiannoutsos

We advocate for a practical Maximum Likelihood Estimation (MLE) approach towards designing loss functions for regression and forecasting, as an alternative to the typical approach of direct empirical risk minimization on a specific target…

Machine Learning · Statistics 2021-10-12 Pranjal Awasthi , Abhimanyu Das , Rajat Sen , Ananda Theertha Suresh

We consider a semiparametric mixture of two univariate density functions where one of them is known while the weight and the other function are unknown. Such mixtures have a history of application to the problem of detecting differentially…

Statistics Theory · Mathematics 2017-08-01 Zhou Shen , Michael Levine , Zuofeng Shang

Expectation Maximization (EM) is among the most popular algorithms for maximum likelihood estimation, but it is generally only guaranteed to find its stationary points of the log-likelihood objective. The goal of this article is to present…

Machine Learning · Computer Science 2018-10-29 Ji Xu , Daniel Hsu , Arian Maleki

Finite mixture modelling is a popular method in the field of clustering and is beneficial largely due to its soft cluster membership probabilities. A common method for fitting finite mixture models is to employ spectral clustering, which…

Machine Learning · Statistics 2024-03-22 Liam Welsh , Phillip Shreeves

This paper is concerned with learning of mixture regression models for individuals that are measured repeatedly. The adjective "unsupervised" implies that the number of mixing components is unknown and has to be determined, ideally by data…

Methodology · Statistics 2018-01-09 Peirong Xu , Heng Peng , Tao Huang

Regression models, where the response variable is circular, are common in areas such as biology, geology and meteorology. A typical model assumes that the conditional distribution of the response follows a von-Mises distribution. However,…

Methodology · Statistics 2026-01-12 Sphiwe B. Skhosana , Najmeh Nakhaei Rad

We introduce a general framework for regression in the errors-in-variables regime, allowing for full flexibility about the dimensionality of the data, observational error probability density types, the (nonlinear) model type and the…

Methodology · Statistics 2024-11-19 Wolfgang Hoegele , Sarah Brockhaus

We present a new nonparametric mixture-of-experts model for multivariate regression problems, inspired by the probabilistic k-nearest neighbors algorithm. Using a conditionally specified model, predictions for out-of-sample inputs are based…

Machine Learning · Statistics 2022-08-05 Tianfang Zhang , Rasmus Bokrantz , Jimmy Olsson

This paper introduces a novel mixture model-based approach for simultaneous clustering and optimal segmentation of functional data which are curves presenting regime changes. The proposed model consists in a finite mixture of piecewise…

Methodology · Statistics 2014-05-02 Faicel Chamroukhi

In this paper, we develop a simulation-based framework for regularized logistic regression, exploiting two novel results for scale mixtures of normals. By carefully choosing a hierarchical model for the likelihood by one type of mixture,…

Methodology · Statistics 2015-03-17 Robert B. Gramacy , Nicholas G. Polson

We study modeling and inference with the Elliptical Gamma Distribution (EGD). We consider maximum likelihood (ML) estimation for EGD scatter matrices, a task for which we develop new fixed-point algorithms. Our algorithms are efficient and…

Computation · Statistics 2018-06-04 Reshad Hosseini , Suvrit Sra , Lucas Theis , Matthias Bethge

Mixture models serve as one fundamental tool with versatile applications. However, their training techniques, like the popular Expectation Maximization (EM) algorithm, are notoriously sensitive to parameter initialization and often suffer…

Machine Learning · Computer Science 2023-12-20 Yulai Cong , Sijia Li

Multivariate meta-analysis is gaining prominence in evidence synthesis research because it enables simultaneous synthesis of multiple correlated outcome data, and random-effects models have generally been used for addressing between-studies…

Methodology · Statistics 2021-07-14 Hisashi Noma , Kengo Nagashima , Toshi A. Furukawa

This paper studies the high-dimensional mixed linear regression (MLR) where the output variable comes from one of the two linear regression models with an unknown mixing proportion and an unknown covariance structure of the random…

Methodology · Statistics 2020-11-10 Linjun Zhang , Rong Ma , T. Tony Cai , Hongzhe Li

The Mixture Transition Distribution (MTD) model was introduced by Raftery to face the need for parsimony in the modeling of high-order Markov chains in discrete time. The particularity of this model comes from the fact that the effect of…

Computation · Statistics 2008-12-18 Sophie Lèbre , Pierre-Yves Bourguinon

Item response theory (IRT) models typically rely on a normality assumption for subject-specific latent traits, which is often unrealistic in practice. Semiparametric extensions based on Dirichlet process mixtures offer a more flexible…