English
Related papers

Related papers: The Helicoidal Method

200 papers

We review the literature on algorithms for estimating the index space in a multi-index model. The primary focus is on computationally efficient (polynomial-time) algorithms in Gaussian space, the assumptions under which consistency is…

Machine Learning · Statistics 2025-06-17 Joan Bruna , Daniel Hsu

In this paper, we suggest a new heterogeneous multiscale method (HMM) for the time-harmonic Maxwell equations in locally periodic media. The method is constructed by using a divergence-regularization in one of the cell problems. This allows…

Numerical Analysis · Mathematics 2015-09-15 Patrick Henning , Mario Ohlberger , Barbara Verfürth

We consider the identifiability and stable numerical estimation of multiple parameters in a Cahn-Hilliard model for phase separation. Spatially resolved measurements of the phase fraction are assumed to be accessible, with which the…

Numerical Analysis · Mathematics 2023-05-03 Aaron Brunk , Herbert Egger , Oliver Habrich

In this article, we propose new Bayesian methods for selecting and estimating a sparse coefficient vector for skewed heteroscedastic response. Our novel Bayesian procedures effectively estimate the median and other quantile functions,…

Methodology · Statistics 2017-07-04 Libo Wang , Yuanyuan Tang , Debajyoti Sinha , Debdeep Pati , Stuart Lipsitz

We consider the problem of inference for non-stationary time series with heavy-tailed error distribution. Under a time-varying linear process framework we show that there exists a suitable local approximation by a stationary process with…

Statistics Theory · Mathematics 2024-07-09 Fumiya Akashi , Konstantinos Fokianos , Junichi Hirukawa

Attempts to incorporate topological information in supervised learning tasks have resulted in the creation of several techniques for vectorizing persistent homology barcodes. In this paper, we study thirteen such methods. Besides describing…

Statistical multispecies models of multiarea marine ecosystems use a variety of data sources to estimate parameters using composite or weighted likelihood functions with associated weighting issues and questions on how to obtain variance…

Applications · Statistics 2012-02-16 Lorna Taylor , Verena M. Trenkel , Vojtech Kupca , Gunnar Stefansson

The time integration of semilinear parabolic problems by exponential methods of different kinds is considered. A new algorithm for the implementation of these methods is proposed. The algorithm evaluates the operators required by the…

Numerical Analysis · Mathematics 2008-10-23 Maria Lopez-Fernandez

We obtain a complete characterization of the weak-type $(1,1)$ for Haar shift operators in terms of generalized Haar systems adapted to a Borel measure $\mu$ in the operator-valued setting. The main technical tool in our method is a…

Classical Analysis and ODEs · Mathematics 2014-12-17 José M. Conde-Alonso , Luis Daniel López-Sánchez

Stochastic differential equations have been an important tool in modeling complex financial relations, equipped with the possibility of being multidimensional to better oversee complexities inherent in finance. This multidimensionality,…

Mathematical Finance · Quantitative Finance 2025-08-22 Ahmet Umur Özsoy

This review article focuses on regularised estimation procedures applicable to geostatistical and spatial econometric models. These methods are particularly relevant in the case of big geospatial data for dimensionality reduction or model…

Methodology · Statistics 2026-04-30 Philipp Otto , Alessandro Fassò , Paolo Maranzano

This paper presents a backfitting-type method for estimating and forecasting a periodically correlated partially linear model with exogeneous variables and heteroskedastic input noise. A rate of convergence of the estimator is given. The…

Statistics Theory · Mathematics 2011-02-23 Xavier Brossat , Georges Oppenheim , Marie-Claude Viano

We give new proofs of Hardy space estimates for fractional and singular integral operators on weighted and variable exponent Hardy spaces. Our proofs consist of several interlocking ideas: finite atomic decompositions in terms of $L^\infty$…

Classical Analysis and ODEs · Mathematics 2019-02-12 David Cruz-Uribe , Kabe Moen , Hanh Nguyen

Synthetic control methods can produce misleading counterfactual predictions when outcome series contain unit-specific stochastic trends, a common feature of nonstationary macroeconomic data. Existing remedies, such as pre-filtering or…

Econometrics · Economics 2026-05-21 Ziyi Liu , Yiqing Xu

Hamiltonian Boundary Value Methods (in short, HBVMs) is a new class of numerical methods for the efficient numerical solution of canonical Hamiltonian systems. In particular, their main feature is that of exactly preserving, for the…

Numerical Analysis · Mathematics 2010-02-24 Luigi Brugnano , Felice Iavernaro , Donato Trigiante

Stacking, a potent ensemble learning method, leverages a meta-model to harness the strengths of multiple base models, thereby enhancing prediction accuracy. Traditional stacking techniques typically utilize established learning models, such…

Machine Learning · Computer Science 2024-10-31 Wei Wu , Liang Tang , Zhongjie Zhao , Chung-Piaw Teo

A methodology for computing expansion basis functions using discrete harmonic modes is presented. The discrete harmonic modes are determined grain-by-grain for virtual polycrystals for which finite element meshes are available. The…

Materials Science · Physics 2021-03-10 Paul R. Dawson , Matthew P. Miller

Heteroskedastic errors can lead to inaccurate statistical conclusions if they are not properly handled. We introduce a test for heteroskedasticity for the nonparametric regression model with multiple covariates. It is based on a suitable…

Methodology · Statistics 2018-02-21 Justin Chown , Ursula U. Müller

Latent variable models are increasingly used in economics for high-dimensional categorical data like text and surveys. We demonstrate the effectiveness of Hamiltonian Monte Carlo (HMC) with parallelized automatic differentiation for…

Econometrics · Economics 2024-03-04 Szymon Sacher , Laura Battaglia , Stephen Hansen

Supervised operator learning centers on the use of training data, in the form of input-output pairs, to estimate maps between infinite-dimensional spaces. It is emerging as a powerful tool to complement traditional scientific computing,…

Machine Learning · Computer Science 2024-08-14 Nicholas H. Nelsen , Andrew M. Stuart