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Related papers: Isotropic and anisotropic pointing models

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Non linear regression models are a standard tool for modeling real phenomena, with several applications in machine learning, ecology, econometry... Estimating the parameters of the model has garnered a lot of attention during many years. We…

Statistics Theory · Mathematics 2020-09-17 Peggy Cénac , Antoine Godichon-Baggioni , Bruno Portier

We implement the efficient line of sight method to calculate the anisotropy and polarization of the cosmic microwave background for scalar and tensor modes in almost-Friedmann-Robertson-Walker models with positive spatial curvature. We…

Astrophysics · Physics 2008-11-26 Antony Lewis , Anthony Challinor , Anthony Lasenby

The partially linear binary choice model can be used for estimating structural equations where nonlinearity may appear due to diminishing marginal returns, different life cycle regimes, or hectic physical phenomena. The inference procedure…

Econometrics · Economics 2023-12-01 Wenzheng Gao , Zhenting Sun

Finding a Z-eigenpair of a symmetric tensor is equivalent to finding a KKT point of a sphere constrained minimization problem. Based on this equivalency, in this paper, we first propose a class of iterative methods to get a Z-eigenpair of a…

Optimization and Control · Mathematics 2022-03-15 Dong-hui Li , Xueli Bai , Jiefeng Xu

We describe an approach to improving model fitting and model generalization that considers the entropy of distributions of modelling residuals. We use simple simulations to demonstrate the observational signatures of overfitting on ordered…

Methodology · Statistics 2019-08-05 Barnaby Rowe

This paper presents a hybrid numerical method to solve efficiently a class of highly anisotropic elliptic problems. The anisotropy is aligned with one coordinate-axis and its strength is described by a parameter $\eps \in (0,1]$, which can…

Numerical Analysis · Mathematics 2015-11-04 Anais Crestetto , Fabrice Deluzet , Claudia Negulescu

We consider the surface critical behaviour of diagonally layered Ising models on the square lattice where the inter-layer couplings follow some aperiodic sequence. The surface magnetisation is analytically evaluated from a simple formula…

Condensed Matter · Physics 2009-10-28 Ferenc Igloi , Peter Lajko

A common approach for generating an anisotropic mesh is the M-uniform mesh approach where an adaptive mesh is generated as a uniform one in the metric specified by a given tensor M. A key component is the determination of an appropriate…

Numerical Analysis · Mathematics 2012-10-11 Lennard Kamenski

We show how the spontaneous bulk, surface and corner magnetizations in the square lattice Ising model can all be obtained within one approach. The method is based on functional equations which follow from the properties of corner transfer…

Statistical Mechanics · Physics 2009-10-28 Brian Davies , Ingo Peschel

This paper focuses on regularisation methods using models up to the third order to search for up to second-order critical points of a finite-sum minimisation problem. The variant presented belongs to the framework of [3]: it employs random…

Numerical Analysis · Mathematics 2021-04-05 Stefania Bellavia , Gianmarco Gurioli , Benedetta Morini , Philippe L. Toint

A methodology for using random sketching in the context of model order reduction for high-dimensional parameter-dependent systems of equations was introduced in [Balabanov and Nouy 2019, Part I]. Following this framework, we here construct…

Numerical Analysis · Mathematics 2022-03-25 Oleg Balabanov , Anthony Nouy

The paper addresses the model reduction problem by least squares moment matching for continuous-time, linear, time-invariant systems. The basic idea behind least squares moment matching is to approximate a transfer function by ensuring that…

Optimization and Control · Mathematics 2021-09-27 Alberto Padoan

Many adaptive mesh methods explicitly or implicitly use equidistribution and alignment. These principles can be considered central to mesh adaption. A Metric Tensor is the tool by which one describes the desired level of mesh anisotropy. In…

Numerical Analysis · Mathematics 2014-02-25 C. J. Budd , R. D. Russell , E. Walsh

In this paper, we propose crossing statistics and its generalization, as a new framework to characterize the anisotropy in a 2D field, e.g. height on a surface, extendable to higher dimensions. By measuring $\nu^+$, the number of…

Computational Physics · Physics 2018-10-12 M. Ghasemi Nezhadhaghighi , S. M. S. Movahed , T. Yasseri , S. M. Vaez Allaei

The estimation of parameter standard errors for semi-variogram models is challenging, given the two-step process required to fit a parametric model to spatially correlated data. Motivated by an application in the social-epidemiology, we…

Methodology · Statistics 2023-07-18 Julia Dyck , Odile Sauzet

The paper is concerned with the inverse scattering problem for Maxwell's equations in three dimensional anisotropic periodic media. We study a new imaging functional for fast and stable reconstruction of the shape of anisotropic periodic…

Numerical Analysis · Mathematics 2023-06-05 Dinh-Liem Nguyen , Trung Truong

In this paper we introduce a new type of symmetrization, which preserves the anisotropic perimeter of the level sets of a suitable concave smooth function, in order to prove sharp comparison results for solutions of a class of homogeneous…

Analysis of PDEs · Mathematics 2014-10-03 Francesco Della Pietra , Nunzia Gavitone

Tuning parameters are parameters involved in an estimating procedure for the purpose of reducing the risk of some other estimator. Examples include the degree of penalization in penalized regression and likelihood problems, as well as the…

Statistics Theory · Mathematics 2026-03-31 Ingrid Dæhlen , Nils Lid Hjort , Ingrid Hobæk Haff

An element based adaptation method is developed for an anisotropic a posteriori error estimator. The adaptation does not make use of a metric, but instead equidistributes the error over elements using local mesh modifications. Numerical…

Numerical Analysis · Mathematics 2016-12-20 Edward Boey , Yves Bourgault , Thierry Giordano

Several precise and computationally efficient results for pointing errors models in two asymptotic cases are derived in this paper. The normalized mean-squared error (NMSE) performance metric is employed to quantify the accuracy of…

Information Theory · Computer Science 2023-05-11 Maoke Miao , Xiao-yu Chen , Rui Yin , Jiantao Yuan