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Related papers: Copula-based models for correlated circular data

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Normalizing flows, which learn a distribution by transforming the data to samples from a Gaussian base distribution, have proven powerful density approximations. But their expressive power is limited by this choice of the base distribution.…

Machine Learning · Computer Science 2021-07-16 Mike Laszkiewicz , Johannes Lederer , Asja Fischer

In probability and statistics, copulas play important roles theoretically as well as to address a wide range of problems in various application areas. We introduce the concept of multivariate discrete copulas, discuss their equivalence to…

Methodology · Statistics 2015-12-18 Roman Schefzik

Model selection is an important activity in modern data analysis and the conventional Bayesian approach to this problem involves calculation of marginal likelihoods for different models, together with diagnostics which examine specific…

Computation · Statistics 2008-10-31 David J. Nott , Robert J. Kohn , Mark Fielding

We propose a scalable semiparametric Bayesian model to capture dependencies among multiple neurons by detecting their co-firing (possibly with some lag time) patterns over time. After discretizing time so there is at most one spike at each…

Applications · Statistics 2015-06-22 Babak Shahbaba , Bo Zhou , Shiwei Lan , Hernando Ombao , David Moorman , Sam Behseta

Copulas allow a flexible and simultaneous modeling of complicated dependence structures together with various marginal distributions. Especially if the density function can be represented as the product of the marginal density functions and…

Methodology · Statistics 2020-08-31 Jae Youn Ahn , Sebastian Fuchs , Rosy Oh

Dynamical processes on complex networks such as information propagation, innovation diffusion, cascading failures or epidemic spreading are highly affected by their underlying topologies as characterized by, for instance, degree-degree…

Data Analysis, Statistics and Probability · Physics 2013-03-05 Mathias Raschke , Markus Schläpfer , Konstantinos Trantopoulos

The estimation of dependencies between multiple variables is a central problem in the analysis of financial time series. A common approach is to express these dependencies in terms of a copula function. Typically the copula function is…

Machine Learning · Statistics 2013-07-02 José Miguel Hernández-Lobato , James Robert Lloyd , Daniel Hernández-Lobato

We introduce a general framework for undirected graphical models. It generalizes Gaussian graphical models to a wide range of continuous, discrete, and combinations of different types of data. The models in the framework, called exponential…

Statistics Theory · Mathematics 2019-06-18 Rui Zhuang , Noah Simon , Johannes Lederer

We develop a novel Bayesian method to select important predictors in regression models with multiple responses of diverse types. A sparse Gaussian copula regression model is used to account for the multivariate dependencies between any…

Methodology · Statistics 2020-09-22 Angelos Alexopoulos , Leonardo Bottolo

Risk evaluation is a forecast, and its validity must be backtested. Probability distribution forecasts are used in this work and allow for more powerful validations compared to point forecasts. Our aim is to use bivariate copulas in order…

Risk Management · Quantitative Finance 2023-11-21 Boris David , Gilles Zumbach

We propose a model for unbalanced longitudinal data, where the univariate margins can be selected arbitrarily and the dependence structure is described with the help of a D-vine copula. We show that our approach is an extremely flexible…

Methodology · Statistics 2017-05-18 Matthias Killiches , Claudia Czado

We propose generalized additive partial linear models for complex data which allow one to capture nonlinear patterns of some covariates, in the presence of linear components. The proposed method improves estimation efficiency and increases…

Statistics Theory · Mathematics 2014-05-26 Li Wang , Lan Xue , Annie Qu , Hua Liang

We propose a methodology to explore and measure the pairwise correlations that exist between variables in a dataset. The methodology leverages copulas for encoding dependence between two variables, state-of-the-art optimal transport for…

Machine Learning · Statistics 2016-11-01 Gautier Marti , Sebastien Andler , Frank Nielsen , Philippe Donnat

In geosciences, the use of classical Euclidean methods is unsuitable for treating and analyzing some types of data, as this may not belong to a vector space. This is the case for correlation matrices, belonging to a subfamily of symmetric…

Applications · Statistics 2021-10-04 Alvaro Riquelme

The Copula is widely used to describe the relationship between the marginal distribution and joint distribution of random variables. The estimation of high-dimensional Copula is difficult, and most existing solutions rely either on…

Machine Learning · Computer Science 2022-11-02 Zhi Zeng , Ting Wang

This paper introduces a new class of observation driven dynamic models. The time evolving parameters are driven by innovations of copula form. The resulting models can be made strictly stationary and the innovation term is typically chosen…

Methodology · Statistics 2021-04-05 Landan Zhang , Michael K. Pitt , Robert Kohn

In this work, we show that under specific choices of the copula, the lasso, elastic net, and $g$-prior are particular cases of `copula prior,' for regularization and variable selection method. We present `lasso with Gauss copula prior' and…

Methodology · Statistics 2018-03-14 Rahul Sharma , Sourish Das

We develop factor copula models for analysing the dependence among mixed continuous and discrete responses. Factor copula models are canonical vine copulas that involve both observed and latent variables, hence they allow tail, asymmetric…

Methodology · Statistics 2020-11-18 Sayed H. Kadhem , Aristidis K. Nikoloulopoulos

This paper considers a new family of variational distributions motivated by Sklar's theorem. This family is based on new copula-like densities on the hypercube with non-uniform marginals which can be sampled efficiently, i.e. with a…

Machine Learning · Statistics 2019-12-24 Marcel Hirt , Petros Dellaportas , Alain Durmus

Copula models have been widely used to model the dependence between continuous random variables, but modeling count data via copulas has recently become popular in the statistics literature. Spearman's rho is an appropriate and effective…

Methodology · Statistics 2020-12-21 Hadi Safari-Katesari , S. Yaser Samadi , Samira Zaroudi