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Related papers: Generalised Wishart Processes

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We develop simple methods for constructing parameter priors for model choice among Directed Acyclic Graphical (DAG) models. In particular, we introduce several assumptions that permit the construction of parameter priors for a large number…

Machine Learning · Statistics 2021-07-01 Dan Geiger , David Heckerman

Multivariate regression techniques are commonly applied to explore the associations between large numbers of outcomes and predictors. In real-world applications, the outcomes are often of mixed types, including continuous measurements,…

Methodology · Statistics 2020-10-19 Aditya Mishra , Dipak K. Dey , Yong Chen , Kun Chen

Research on Poisson regression analysis for dependent data has been developed rapidly in the last decade. One of difficult problems in a multivariate case is how to construct a cross-correlation structure and at the meantime make sure that…

Methodology · Statistics 2017-10-05 A'yunin Sofro , Jian Qing Shi , Chunzheng Cao

We introduce a Gaussian process-based model for handling of non-stationarity. The warping is achieved non-parametrically, through imposing a prior on the relative change of distance between subsequent observation inputs. The model allows…

Machine Learning · Statistics 2019-12-06 David Tolpin

Wishart random matrices with a sparse or diluted structure are ubiquitous in the processing of large datasets, with applications in physics, biology and economy. In this work we develop a theory for the eigenvalue fluctuations of diluted…

Disordered Systems and Neural Networks · Physics 2018-03-20 Isaac Pérez Castillo , Fernando L. Metz

We consider a short rate model, driven by a stochastic process on the cone of positive semidefinite matrices. We derive sufficient conditions ensuring that the model replicates normal, inverse or humped yield curves.

Pricing of Securities · Quantitative Finance 2014-05-08 Alessandro Gnoatto

Recent work has explored data thinning, a generalization of sample splitting that involves decomposing a (possibly matrix-valued) random variable into independent components. In the special case of a $n \times p$ random matrix with…

Methodology · Statistics 2025-12-16 Ameer Dharamshi , Anna Neufeld , Lucy L. Gao , Daniela Witten , Jacob Bien

Wishart ensemble is a useful and important random matrix model used in diverse fields. By realizing induced random mixed quantum states as Wishart ensemble with the fixed-trace one, using matrix integral technique we give a fast track to…

Quantum Physics · Physics 2017-03-22 Lin Zhang

This paper deals with the Elliptical Wishart and Inverse Elliptical Wishart distributions, which play a major role when handling covariance matrices. Similarly to multivariate elliptical distributions, these form a large family of…

Statistics Theory · Mathematics 2024-11-01 Imen Ayadi , Florent Bouchard , Frédéric Pascal

In complex systems, crucial parameters are often subject to unpredictable changes in time. Climate, biological evolution and networks provide numerous examples for such non-stationarities. In many cases, improved statistical models are…

Statistical Finance · Quantitative Finance 2015-12-09 Frederik Meudt , Martin Theissen , Rudi Schäfer , Thomas Guhr

We define a copula process which describes the dependencies between arbitrarily many random variables independently of their marginal distributions. As an example, we develop a stochastic volatility model, Gaussian Copula Process Volatility…

Methodology · Statistics 2010-06-24 Andrew Gordon Wilson , Zoubin Ghahramani

We investigate the Student-t process as an alternative to the Gaussian process as a nonparametric prior over functions. We derive closed form expressions for the marginal likelihood and predictive distribution of a Student-t process, by…

Machine Learning · Statistics 2014-02-20 Amar Shah , Andrew Gordon Wilson , Zoubin Ghahramani

This paper presents a new variable selection approach integrated with Gaussian process (GP) regression. We consider a sparse projection of input variables and a general stationary covariance model that depends on the Euclidean distance…

Machine Learning · Computer Science 2020-08-26 Chiwoo Park , David J. Borth , Nicholas S. Wilson , Chad N. Hunter

Deep Gaussian Processes learn probabilistic data representations for supervised learning by cascading multiple Gaussian Processes. While this model family promises flexible predictive distributions, exact inference is not tractable.…

Machine Learning · Statistics 2020-10-23 Jakob Lindinger , David Reeb , Christoph Lippert , Barbara Rakitsch

A characterization of the existence of non-central Wishart distributions (with shape and non-centrality parameter) as well as the existence of solutions to Wishart stochastic differential equations (with initial data and drift parameter) in…

Probability · Mathematics 2019-01-29 Piotr Graczyk , Jacek Malecki , Eberhard Mayerhofer

Standard penalized methods of variable selection and parameter estimation rely on the magnitude of coefficient estimates to decide which variables to include in the final model. However, coefficient estimates are unreliable when the design…

Methodology · Statistics 2018-02-13 Jonathan P Williams , Jan Hannig

We introduce graph gamma process (GGP) linear dynamical systems to model real-valued multivariate time series. For temporal pattern discovery, the latent representation under the model is used to decompose the time series into a…

Methodology · Statistics 2020-07-28 Rahi Kalantari , Mingyuan Zhou

Credible forecasting and representation learning of dynamical systems are of ever-increasing importance for reliable decision-making. To that end, we propose a family of Gaussian processes (GP) for dynamical systems with linear…

Machine Learning · Computer Science 2025-02-11 Petar Bevanda , Max Beier , Armin Lederer , Alexandre Capone , Stefan Sosnowski , Sandra Hirche

By using a symbolic method, known in the literature as the classical umbral calculus, the trace of a non-central Wishart random matrix is represented as the convolution of the trace of its central component and of a formal variable…

Statistics Theory · Mathematics 2014-07-30 Elvira Di Nardo

A semi-analytic method is proposed for the generation of realizations of a multivariate process of a given linear correlation structure and marginal distribution. This is an extension of a similar method for univariate processes,…

Computation · Statistics 2014-03-14 Dimitris Kugiumtzis , Efthimia Bora-Senta