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We present the R-package mgm for the estimation of k-order Mixed Graphical Models (MGMs) and mixed Vector Autoregressive (mVAR) models in high-dimensional data. These are a useful extensions of graphical models for only one variable type,…

Applications · Statistics 2020-02-13 Jonas M. B. Haslbeck , Lourens J. Waldorp

Additive smooth models, such as Generalized additive models (GAMs) of location, scale, and shape (GAMLSS), are a popular choice for modeling experimental data. However, software available to fit such models is usually not tailored…

Methodology · Statistics 2025-06-17 Joshua Krause , Jelmer P. Borst , Jacolien van Rij

To deal with very large datasets a mini-batch version of the Monte Carlo Markov Chain Stochastic Approximation Expectation-Maximization algorithm for general latent variable models is proposed. For exponential models the algorithm is shown…

Computation · Statistics 2023-08-30 Tabea Rebafka , Estelle Kuhn , Catherine Matias

Model ensembling is a well-established technique for improving the performance of machine learning models. Conventionally, this involves averaging the output distributions of multiple models and selecting the most probable label. This idea…

Machine Learning · Computer Science 2026-05-26 Jiale Fu , Yuchu Jiang , Peijun Wu , Chonghan Liu , Joey Tianyi Zhou , Xu Yang

Exponential random graph models (ERGMs) are widely used for modeling social networks observed at one point in time. However the computational difficulty of ERGM parameter estimation has limited the practical application of this class of…

Methodology · Statistics 2021-11-24 Alex Stivala , Garry Robins , Alessandro Lomi

Expectation maximization (EM) algorithm is to find maximum likelihood solution for models having latent variables. A typical example is Gaussian Mixture Model (GMM) which requires Gaussian assumption, however, natural images are highly…

Machine Learning · Computer Science 2018-12-04 Wentian Zhao , Shaojie Wang , Zhihuai Xie , Jing Shi , Chenliang Xu

We present a new version of the truncated harmonic mean estimator (THAMES) for univariate or multivariate mixture models. The estimator computes the marginal likelihood from Markov chain Monte Carlo (MCMC) samples, is consistent,…

We use the theory of normal variance-mean mixtures to derive a data augmentation scheme for models that include gamma functions. Our methodology applies to many situations in statistics and machine learning, including Multinomial-Dirichlet…

Methodology · Statistics 2021-06-22 Jingyu He , Nicholas Polson , Jianeng Xu

In portfolio analysis, the traditional approach of replacing population moments with sample counterparts may lead to suboptimal portfolio choices. I show that optimal portfolio weights can be estimated using a machine learning (ML)…

Portfolio Management · Quantitative Finance 2018-07-31 Daniel Kinn

We show that the estimating equations for quantile regression can be solved using a simple EM algorithm in which the M-step is computed via weighted least squares, with weights computed at the E-step as the expectation of independent…

Methodology · Statistics 2021-06-29 Haim Y. Bar , James G. Booth , Martin T. Wells

Linear Mixed Effects (LME) models have been widely applied in clustered data analysis in many areas including marketing research, clinical trials, and biomedical studies. Inference can be conducted using maximum likelihood approach if…

Methodology · Statistics 2022-11-10 Hao Chen , Lanshan Han , Alvin Lim

The normality assumption on data set is very restrictive approach for modelling. The generalized form of normal distribution, named as an exponential power (EP) distribution, and its scale mixture form have been considered extensively to…

Statistics Theory · Mathematics 2017-07-20 Mehmet Niyazi Cankaya , Olcay Arslan

We propose an Gaussian Mixture Model (GMM) learning algorithm, based on our previous work of GMM expansion idea. The new algorithm brings more robustness and simplicity than classic Expectation Maximization (EM) algorithm. It also improves…

Machine Learning · Computer Science 2023-09-07 Weiguo Lu , Xuan Wu , Deng Ding , Gangnan Yuan

Mixture models have attracted significant attention due to practical effectiveness and comprehensive theoretical foundations. A persisting challenge is model misspecification, which occurs when the model to be fitted has more mixture…

Machine Learning · Computer Science 2026-03-09 Zhankun Luo , Abolfazl Hashemi

We give convergence guarantees for estimating the coefficients of a symmetric mixture of two linear regressions by expectation maximization (EM). In particular, we show that the empirical EM iterates converge to the target parameter vector…

Machine Learning · Statistics 2018-10-17 Jason M. Klusowski , Dana Yang , W. D. Brinda

The performance of ensemble-based data assimilation techniques that estimate the state of a dynamical system from partial observations depends crucially on the prescribed uncertainty of the model dynamics and of the observations. These are…

Computation · Statistics 2021-02-24 Tadeo Javier Cocucci , Manuel Pulido , Magdalena Lucini , Pierre Tandeo

A line of recent work has analyzed the behavior of the Expectation-Maximization (EM) algorithm in the well-specified setting, in which the population likelihood is locally strongly concave around its maximizing argument. Examples include…

Statistics Theory · Mathematics 2020-04-30 Raaz Dwivedi , Nhat Ho , Koulik Khamaru , Michael I. Jordan , Martin J. Wainwright , Bin Yu

By recognizing that the main difficulty of the modeling of daily precipitation amounts is the selection of an appropriate probability distribution, this study aims to establish a model selection framework to identify the appropriate…

Applications · Statistics 2020-09-01 Hsien-Wei Chen

The Expectation-Maximization (EM) algorithm is an iterative method to maximize the log-likelihood function for parameter estimation. Previous works on the convergence analysis of the EM algorithm have established results on the asymptotic…

Statistics Theory · Mathematics 2017-05-31 Chong Wu , Can Yang , Hongyu Zhao , Ji Zhu

Randomized neural networks (NNs) are an interesting alternative to conventional NNs that are more used for data modeling. The random vector functional-link (RVFL) network is an established and theoretically well-grounded randomized learning…

Computation · Statistics 2018-04-24 Hien D. Nguyen , Dianhui Wang , Geoffrey J. McLachlan