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Data assimilation is a method that combines observations (that is, real world data) of a state of a system with model output for that system in order to improve the estimate of the state of the system and thereby the model output. The model…

Numerical Analysis · Mathematics 2020-05-18 Melina A. Freitag

Distance covariance is a widely used statistical methodology for testing the dependency between two groups of variables. Despite the appealing properties of consistency and superior testing power, the testing results of distance covariance…

Methodology · Statistics 2026-03-20 Andi Wang , Hao Yan , Juan Du

Data Assimilation (DA) and Uncertainty quantification (UQ) are extensively used in analysing and reducing error propagation in high-dimensional spatial-temporal dynamics. Typical applications span from computational fluid dynamics (CFD) to…

Distance covariance and distance correlation have been widely adopted in measuring dependence of a pair of random variables or random vectors. If the computation of distance covariance and distance correlation is implemented directly…

Computation · Statistics 2014-10-07 Xiaoming Huo , Gabor J. Szekely

Recent advances in data assimilation (DA) have focused on developing more flexible approaches that can better accommodate nonlinearities in models and observations. However, it remains unclear how the performance of these advanced methods…

Atmospheric and Oceanic Physics · Physics 2025-05-08 Zixiang Xiong , Siming Liang , Feng Bao , Guannan Zhang , Hristo G. Chipilski

This paper presents a new variational data assimilation (VDA) approach for the formal treatment of bias in both model outputs and observations. This approach relies on the Wasserstein metric stemming from the theory of optimal mass…

Methodology · Statistics 2020-08-04 Sagar K. Tamang , Ardeshir Ebtehaj , Dongmian Zou , Gilad Lerman

Marine biogeochemistry models are critical for forecasting, as well as estimating ecosystem responses to climate change and human activities. Data assimilation (DA) improves these models by aligning them with real-world observations, but…

Atmospheric and Oceanic Physics · Physics 2025-04-08 Ieuan Higgs , Ross Bannister , Jozef Skákala , Alberto Carrassi , Stefano Ciavatta

Data assimilation (DA) provides a general framework for estimation in dynamical systems based on the concepts of Bayesian inference. This constitutes a common basis for the different linear and nonlinear filtering and smoothing techniques…

Optimization and Control · Mathematics 2023-03-08 Tarek Diaa-Eldeen , Marcus Krogh Nielsen , Carl Fredrik Berg , Morten Hovd , John Bagterp Jørgensen

Data assimilation is an iterative approach to the problem of estimating the state of a dynamical system using both current and past observations of the system together with a model for the system's time evolution. Rather than solving the…

Data Analysis, Statistics and Probability · Physics 2007-05-23 Brian R. Hunt , Eric J. Kostelich , Istvan Szunyogh

A novel strategy is proposed to improve the accuracy of state estimation and reconstruction from low-fidelity models and sparse data from sensors. This strategy combines ensemble Data Assimilation (DA) and Machine Learning (ML) tools,…

Fluid Dynamics · Physics 2025-01-31 Miguel M. Valero , Marcello Meldi

Data assimilation (DA) combines model forecasts and observations to estimate the optimal state of the atmosphere with its uncertainty, providing initial conditions for weather prediction and reanalyses for climate research. Yet, existing…

Machine Learning · Computer Science 2026-03-05 Hang Fan , Juan Nathaniel , Yi Xiao , Ce Bian , Fenghua Ling , Ben Fei , Lei Bai , Pierre Gentine

Variational data assimilation optimizes for an initial state of a dynamical system such that its evolution fits observational data. The physical model can subsequently be evolved into the future to make predictions. This principle is a…

Machine Learning · Computer Science 2021-05-21 Thomas Frerix , Dmitrii Kochkov , Jamie A. Smith , Daniel Cremers , Michael P. Brenner , Stephan Hoyer

Data assimilation combines forecasts from a numerical model with observations. Most of the current data assimilation algorithms consider the model and observation error terms as additive Gaussian noise, specified by their covariance…

Cooperative geolocation has attracted significant research interests in recent years. A large number of localization algorithms rely on the availability of statistical knowledge of measurement errors, which is often difficult to obtain in…

Applications · Statistics 2017-01-05 Xiufang Shi , Guoqiang Mao , Brian. D. O. Anderson , Zaiyue Yang , Jiming Chen

Data assimilation refers to the process of obtaining an estimate of a system's state using a model for the system's time evolution and a time series of measurements that are possibly noisy and incomplete. However, for practical reasons, the…

Chaotic Dynamics · Physics 2007-05-23 Matthew Cornick , Brian Hunt , Edward Ott , Michael F. Schatz

Indoor localization is a challenging problem that - unlike outdoor localization - lacks a universal and robust solution. Machine Learning (ML), particularly Deep Learning (DL), methods have been investigated as a promising approach.…

Systems and Control · Electrical Eng. & Systems 2024-08-29 Omer Gokalp Serbetci , Daoud Burghal , Andreas F. Molisch

The integration of observational data into numerical models, known as data assimilation (DA), is fundamental for making Numerical Weather Prediction (NWP) possible, with breathtaking success over the past 60 years (Bauer et al. 2015).…

Atmospheric and Oceanic Physics · Physics 2024-06-04 Jan D. Keller , Roland Potthast

Data assimilation algorithms estimate the state of a dynamical system from partial observations, where the successful performance of these algorithms hinges on costly parameter tuning and on employing an accurate model for the dynamics.…

Machine Learning · Statistics 2026-03-24 Melissa Adrian , Daniel Sanz-Alonso , Rebecca Willett

Many dynamical systems are difficult or impossible to model using high fidelity physics based models. Consequently, researchers are relying more on data driven models to make predictions and forecasts. Based on limited training data,…

Chaotic Dynamics · Physics 2025-04-09 Max M. Chumley , Firas A. Khasawneh

We consider the inference problem for high-dimensional linear models, when covariates have an underlying spatial organization reflected in their correlation. A typical example of such a setting is high-resolution imaging, in which…

Methodology · Statistics 2021-06-07 Jérôme-Alexis Chevalier , Tuan-Binh Nguyen , Bertrand Thirion , Joseph Salmon