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A multiscale numerical method is proposed for the solution of semi-linear elliptic stochastic partial differential equations with localized uncertainties and non-linearities, the uncertainties being modeled by a set of random parameters. It…

Numerical Analysis · Mathematics 2019-01-23 Anthony Nouy , Florent Pled

We propose a model of random walks on weighted graphs where the weights are interval valued, and connect it to reversible imprecise Markov chains. While the theory of imprecise Markov chains is now well established, this is a first attempt…

Optimization and Control · Mathematics 2016-09-20 Damjan Škulj

Anomaly detection is a challenging problem in intelligent video surveillance. Most existing methods are computation consuming, which cannot satisfy the real-time requirement. In this paper, we propose a real-time anomaly detection framework…

Computer Vision and Pattern Recognition · Computer Science 2018-12-13 Huihui Zhu , Bin Liu , Guojun Yin , Yan Lu , Weihai Li , Nenghai Yu

This paper presents a methodology for solving a geometrically robust least squares problem, which arises in various applications where the model is subject to geometric constraints. The problem is formulated as a minimax optimization…

Optimization and Control · Mathematics 2025-11-06 Jeremy Coulson , Alberto Padoan , Cyrus Mostajeran

Markov Chain Monte Carlo is repeatedly used to analyze the properties of intractable distributions in a convenient way. In this paper we derive conditions for geometric ergodicity of a general class of nonparametric stochastic volatility…

Statistical Finance · Quantitative Finance 2016-12-09 Jerzy P. Rydlewski , Małgorzata Snarska

Bayesian inverse problems often involve sampling posterior distributions on infinite-dimensional function spaces. Traditional Markov chain Monte Carlo (MCMC) algorithms are characterized by deteriorating mixing times upon mesh-refinement,…

Computation · Statistics 2017-03-08 Alexandros Beskos , Mark Girolami , Shiwei Lan , Patrick E. Farrell , Andrew M. Stuart

This paper presents a study using the Bayesian approach in stochastic volatility models for modeling financial time series, using Hamiltonian Monte Carlo methods (HMC). We propose the use of other distributions for the errors in the…

Applications · Statistics 2017-12-07 David S. Dias , Ricardo S. Ehlers

Traditional Markov Chain Monte Carlo methods suffer from low acceptance rate, slow mixing and low efficiency in high dimensions. Hamiltonian Monte Carlo resolves this issue by avoiding the random walk. Hamiltonian Monte Carlo (HMC) is a…

Astrophysics · Physics 2008-11-26 Amir Hajian

The state space representation of active resident space objects can be posed in the form of a stochastic hybrid system. Satellite maneuvers may be accounted for according to control cost or heuristical considerations, yet it is possible to…

Signal Processing · Electrical Eng. & Systems 2022-04-06 Guillermo Escribano , Manuel Sanjurjo-Rivo , Jan Siminski , Alejandro Pastor , Diego Escobar

Hamiltonian Monte Carlo (HMC) has emerged as a powerful Markov Chain Monte Carlo (MCMC) method to sample from complex continuous distributions. However, a fundamental limitation of HMC is that it can not be applied to distributions with…

Computation · Statistics 2021-12-10 Guangyao Zhou

We propose new Markov Chain Monte Carlo algorithms to sample probability distributions on submanifolds, which generalize previous methods by allowing the use of set-valued maps in the proposal step of the MCMC algorithms. The motivation for…

Numerical Analysis · Mathematics 2021-10-07 Tony Lelièvre , Gabriel Stoltz , Wei Zhang

In engineering examples, one often encounters the need to sample from unnormalized distributions with complex shapes that may also be implicitly defined through a physical or numerical simulation model, making it computationally expensive…

Methodology · Statistics 2024-11-27 Promit Chakroborty , Michael D. Shields

We introduce a new identification strategy for uncertainty shocks to explain macroeconomic volatility in financial markets. The Chicago Board Options Exchange Volatility Index (VIX) measures market expectations of future volatility, but…

Econometrics · Economics 2024-11-06 Ayush Jha , Abootaleb Shirvani , Svetlozar T. Rachev , Frank J. Fabozzi

The fundamental theorem behind financial markets is that stock prices are intrinsically complex and stochastic. One of the complexities is the volatility associated with stock prices. Volatility is a tendency for prices to change…

Statistical Finance · Quantitative Finance 2023-11-21 Leonard Mushunje , Maxwell Mashasha , Edina Chandiwana

We consider the problem of finding anomalies in high-dimensional data using popular PCA based anomaly scores. The naive algorithms for computing these scores explicitly compute the PCA of the covariance matrix which uses space quadratic in…

Machine Learning · Computer Science 2018-11-28 Vatsal Sharan , Parikshit Gopalan , Udi Wieder

Visual odometry algorithms tend to degrade when facing low-textured scenes -from e.g. human-made environments-, where it is often difficult to find a sufficient number of point features. Alternative geometrical visual cues, such as lines,…

Computer Vision and Pattern Recognition · Computer Science 2021-11-08 Joan P. Company-Corcoles , Emilio Garcia-Fidalgo , Alberto Ortiz

A number of optimal decision problems with uncertainty can be formulated into a stochastic optimal control framework. The Least-Squares Monte Carlo (LSMC) algorithm is a popular numerical method to approach solutions of such stochastic…

Computational Finance · Quantitative Finance 2019-01-23 Zhiyi Shen , Chengguo Weng

There has been a growing interest in anomaly detection problems recently, whilst their focuses are mostly on anomalies taking place on the time index. In this work, we investigate a new anomaly-in-mean problem in multidimensional spatial…

Methodology · Statistics 2025-10-29 Baiyu Wang , Chao Zheng

Markov Chain Monte Carlo (MCMC) algorithms play an important role in statistical inference problems dealing with intractable probability distributions. Recently, many MCMC algorithms such as Hamiltonian Monte Carlo (HMC) and Riemannian…

Computation · Statistics 2017-04-19 Cheng Zhang , Babak Shahbaba , Hongkai Zhao

The configuration model is a standard tool for uniformly generating random graphs with a specified degree sequence, and is often used as a null model to evaluate how much of an observed network's structure can be explained by its degree…

Social and Information Networks · Computer Science 2023-05-31 Upasana Dutta , Bailey K. Fosdick , Aaron Clauset