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Due to their uncertainty quantification, Bayesian solutions to inverse problems are the framework of choice in applications that are risk averse. These benefits come at the cost of computations that are in general, intractable. New advances…

Machine Learning · Computer Science 2024-05-10 Rafael Orozco , Ali Siahkoohi , Mathias Louboutin , Felix J. Herrmann

We propose two new methods based/inspired by machine learning for tabular data and distance-free localization to enhance the covariance estimations in an ensemble data assimilation. The main goal is to enhance the data assimilation results…

Machine Learning · Computer Science 2025-07-31 Vinicius L. S. Silva , Gabriel S. Seabra , Alexandre A. Emerick

After deployment, machine learning models often experience performance degradation due to shifts in data distribution. It is challenging to assess post-deployment performance accurately when labels are missing or delayed. Existing proxy…

Machine Learning · Computer Science 2025-10-22 Jakub Białek , Juhani Kivimäki , Wojtek Kuberski , Nikolaos Perrakis

Conventional recursive filtering approaches, designed for quantifying the state of an evolving uncertain dynamical system with intermittent observations, use a sequence of (i) an uncertainty propagation step followed by (ii) a step where…

Probability · Mathematics 2015-06-18 Wonjung Lee , Chris Farmer

Quantifying forecast uncertainty is a key aspect of state-of-the-art numerical weather prediction and data assimilation systems. Ensemble-based data assimilation systems incorporate state-dependent uncertainty quantification based on…

Atmospheric and Oceanic Physics · Physics 2023-05-17 Maximiliano A. Sacco , Manuel Pulido , Juan J. Ruiz , Pierre Tandeo

Data assimilation (DA) is widely used to combine physical knowledge and observations. It is nowadays commonly used in geosciences to perform parametric calibration. In a context of climate change, old calibrations can not necessarily be…

Machine Learning · Statistics 2021-06-23 Rem-Sophia Mouradi , Cédric Goeury , Olivier Thual , Fabrice Zaoui , Pablo Tassi

We focus on contrastive methods for self-supervised video representation learning. A common paradigm in contrastive learning is to construct positive pairs by sampling different data views for the same instance, with different data…

Computer Vision and Pattern Recognition · Computer Science 2021-08-23 Chen Sun , Arsha Nagrani , Yonglong Tian , Cordelia Schmid

An important class of nonlinear weighted least-squares problems arises from the assimilation of observations in atmospheric and ocean models. In variational data assimilation, inverse error covariance matrices define the weighting matrices…

Numerical Analysis · Mathematics 2022-12-06 Olivier Goux , Selime Gürol , Anthony T. Weaver , Oliver Guillet , Youssef Diouane

Sparse Inverse Covariance Estimation (SICE) is useful in many practical data analyses. Recovering the connectivity, non-connectivity graph of covariates is classified amongst the most important data mining and learning problems. In this…

Machine Learning · Computer Science 2019-04-05 Ashkan Esmaeili , Farokh Marvasti

Data assimilation has become a key technique for combining physical models with observational data to estimate state variables. However, classical assimilation algorithms often struggle with the high nonlinearity present in both physical…

Machine Learning · Computer Science 2025-07-22 Zhuoyuan Li , Bin Dong , Pingwen Zhang

The 4D-Var method for filtering partially observed nonlinear chaotic dynamical systems consists of finding the maximum a-posteriori (MAP) estimator of the initial condition of the system given observations over a time window, and…

Methodology · Statistics 2021-01-19 Daniel Paulin , Ajay Jasra , Alexandros Beskos , Dan Crisan

Data augmentation plays a critical role in generating high-quality positive and negative pairs necessary for effective contrastive learning. However, common practices involve using a single augmentation policy repeatedly to generate…

Computer Vision and Pattern Recognition · Computer Science 2024-05-14 Nazim Bendib

Datasets from field experiments with covariate-adaptive randomizations (CARs) usually contain extra covariates in addition to the strata indicators. We propose to incorporate these additional covariates via auxiliary regressions in the…

Econometrics · Economics 2022-09-07 Liang Jiang , Peter C. B. Phillips , Yubo Tao , Yichong Zhang

Varying domains and biased datasets can lead to differences between the training and the target distributions, known as covariate shift. Current approaches for alleviating this often rely on estimating the ratio of training and target…

Machine Learning · Statistics 2020-10-27 Bijan Mazaheri , Siddharth Jain , Jehoshua Bruck

We propose a new 'Bi-Reduced Space' approach to solving 3D Variational Data Assimilation using Convolutional Autoencoders. We prove that our approach has the same solution as previous methods but has significantly lower computational…

Machine Learning · Computer Science 2021-01-07 Julian Mack , Rossella Arcucci , Miguel Molina-Solana , Yi-Ke Guo

Covariate adjustment is a ubiquitous method used to estimate the average treatment effect (ATE) from observational data. Assuming a known graphical structure of the data generating model, recent results give graphical criteria for optimal…

Statistics Theory · Mathematics 2025-12-08 Alexander Mangulad Christgau , Anton Rask Lundborg , Niels Richard Hansen

Data assimilation algorithms integrate prior information from numerical model simulations with observed data. Ensemble-based filters, regarded as state-of-the-art, are widely employed for large-scale estimation tasks in disciplines such as…

Numerical Analysis · Mathematics 2024-05-24 Iris Rammelmüller , Gottfried Hastermann , Jana de Wiljes

Data assimilation performance can be significantly impacted by biased noise in observations, altering the signal magnitude and introducing fast oscillations or discontinuities when the system lacks smoothness. To mitigate these issues, this…

Numerical Analysis · Mathematics 2024-11-05 Felipe Galarce , Joaquin Mura , Alfonso Caiazzo

Measurement error arises through a variety of mechanisms. A rich literature exists on the bias introduced by covariate measurement error and on methods of analysis to address this bias. By comparison, less attention has been given to errors…

Methodology · Statistics 2018-11-27 Pamela Shaw , Jiwei He , Bryan Shepherd

Negative sampling is essential for implicit-feedback-based collaborative filtering, which is used to constitute negative signals from massive unlabeled data to guide supervised learning. The state-of-the-art idea is to utilize hard negative…

Information Retrieval · Computer Science 2023-08-14 Yuhan Zhao , Rui Chen , Riwei Lai , Qilong Han , Hongtao Song , Li Chen