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The expectation-maximization (EM) algorithm and its variants are widely used in statistics. In high-dimensional mixture linear regression, the model is assumed to be a finite mixture of linear regression and the number of predictors is much…

Statistics Theory · Mathematics 2023-07-24 Ning Wang , Xin Zhang , Qing Mai

Thermal Doppler broadening of spectral profiles for particle populations in the absence or presence of potential fields are described by kappa distributions. The kappa distribution provides a replacement for the Maxwell-Boltzmann…

Solar and Stellar Astrophysics · Physics 2024-08-01 Arak M. Mathai , Hans J. Haubold

The correct modelling of velocity distribution functions for particles in steady-state plasmas is a central element in the study of nuclear fusion and also in the description of space plasmas. In this work, a statistical mechanical…

Statistical Mechanics · Physics 2019-09-04 Sergio Davis , Gonzalo Avaria , Biswajit Bora , Jalaj Jain , José Moreno , Cristian Pavez , Leopoldo Soto

The recently developed concept of "entropic defect" is important for understanding the foundations of thermodynamics in space plasma physics, and more generally, for systems with physical correlations among their particles. Using this…

Plasma Physics · Physics 2022-11-30 George Livadiotis , David J. McComas

This paper provides a mixture modeling framework using the bivariate generalized exponential distribution. We study different properties of this mixture distribution. Hierarchical EM algorithm is developed for finding the estimates of the…

Computation · Statistics 2018-04-03 Arabin Kumar Dey , Debasis Kundu , Tumati Kiran Kumar

This paper concerns the use of the expectation-maximisation (EM) algorithm for inference in partially observed diffusion processes. In this context, a well known problem is that all except a few diffusion processes lack closed-form…

Statistics Theory · Mathematics 2010-08-18 Jimmy Olsson , Jonas Ströjby

We study the expectation-maximization (EM) algorithm for general latent-variable models under (i) distributional misspecification and (ii) nonidentifiability induced by a group action. We formulate EM on the quotient parameter space and…

Statistics Theory · Mathematics 2026-01-06 Koustav Mallik

In this work we define the plasma dispersion function for a suprathermal plasma described with a regularized kappa distribution. As is known from Maxwellian as well as (standard) kappa plasmas, the respective Fried-Conte and the modified…

Plasma Physics · Physics 2024-11-07 Rudi Gaelzer , Horst Fichtner , Klaus Scherer

This paper deals with parameter estimation when the data are randomly right censored. The maximum likelihood estimates from censored samples are obtained by using the expectation-maximization (EM) and Monte Carlo EM (MCEM) algorithms. We…

Computation · Statistics 2012-03-20 Chanseok Park , Seong Beom Lee

Data assimilation methods aim at estimating the state of a system by combining observations with a physical model. When sequential data assimilation is considered, the joint distribution of the latent state and the observations is described…

Methodology · Statistics 2018-04-23 Thi Tuyet Trang Chau , Pierre Ailliot , Valérie Monbet , Pierre Tandeo

Expectation Propagation (Minka, 2001) is a widely successful algorithm for variational inference. EP is an iterative algorithm used to approximate complicated distributions, typically to find a Gaussian approximation of posterior…

Computation · Statistics 2016-04-01 Guillaume Dehaene , Simon Barthelmé

The velocity particle distributions measured in-situ in space plasmas deviate from Maxwellian (thermal) equilibrium, showing enhanced suprathermal tails which are well described by the standard Kappa-distribution (SKD). Despite its…

Plasma Physics · Physics 2020-06-08 Edin Husidic , Marian Lazar , Horst Fichtner , Klaus Scherer , Patrick Astfalk

We show how the expectation-maximization (EM) algorithm can be applied exactly for the fitting of mixtures of general multivariate skew t (MST) distributions, eliminating the need for computationally expensive Monte Carlo estimation. Finite…

Methodology · Statistics 2012-09-06 S. X. Lee , G. J. McLachlan

In a mixture of linear regression model, the regression coefficients are treated as random vectors that may follow either a continuous or discrete distribution. We propose two Expectation-Maximization (EM) algorithms to estimate this prior…

Methodology · Statistics 2025-10-17 Andrew Welbaum , Wanli Qiao

Over the past decades, there has been a surge of interest in studying low-dimensional structures within high-dimensional data. Statistical factor models $-$ i.e., low-rank plus diagonal covariance structures $-$ offer a powerful framework…

Machine Learning · Statistics 2025-05-20 Daniel Cederberg

Finite mixture models are among the most popular statistical models used in different data science disciplines. Despite their broad applicability, inference under these models typically leads to computationally challenging non-convex…

Machine Learning · Computer Science 2018-09-25 Babak Barazandeh , Meisam Razaviyayn

Expectation Maximization (EM) is among the most popular algorithms for estimating parameters of statistical models. However, EM, which is an iterative algorithm based on the maximum likelihood principle, is generally only guaranteed to find…

Statistics Theory · Mathematics 2016-08-30 Ji Xu , Daniel Hsu , Arian Maleki

In this paper, we present an algorithm for the fitting of a location-scale variant of the canonical fundamental skew t (CFUST) distribution, a superclass of the restricted and unrestricted skew t-distributions. In recent years, a few…

Methodology · Statistics 2014-02-03 Sharon X. Lee , Geoffrey J. McLachlan

Heckman selection model is perhaps the most popular econometric model in the analysis of data with sample selection. The analyses of this model are based on the normality assumption for the error terms, however, in some applications, the…

Methodology · Statistics 2020-06-16 Victor H. Lachos Davila , Marcos O. Prates , Dipak K. Dey

Exponential family distributions are highly useful in machine learning since their calculation can be performed efficiently through natural parameters. The exponential family has recently been extended to the t-exponential family, which…

Machine Learning · Statistics 2017-05-30 Futoshi Futami , Issei Sato , Masashi Sugiyama