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Completely nonparametric transformation models with heteroscedastic errors are considered. Despite their flexibility, such models have rarely been used so far, since estimators of the model components have been missing and even…

Statistics Theory · Mathematics 2020-04-07 Nick Kloodt

A longstanding open problem in lambda calculus is whether there exist continuous models of the untyped lambda calculus whose theory is exactly the least lambda-theory lambda-beta or the least sensible lambda-theory H (generated by equating…

Logic in Computer Science · Computer Science 2013-04-01 Antonio Bucciarelli , Alberto Carraro , Antonino Salibra

We consider here estimation of an unknown probability density s belonging to L2(mu) where mu is a probability measure. We have at hand n i.i.d. observations with density s and use the squared L2-norm as our loss function. The purpose of…

Statistics Theory · Mathematics 2013-01-22 Lucien Birgé

We study two types of entropic-force models in a homogeneous, isotropic, spatially flat, matter-dominated universe. The first type is a `$\Lambda(t)$ type' similar to $\Lambda(t)$CDM (varying-lambda cold dark matter) models in which both…

Cosmology and Nongalactic Astrophysics · Physics 2014-06-11 Nobuyoshi Komatsu , Shigeo Kimura

We consider a real-world scenario in which a newly-established pilot project needs to make inferences for newly-collected data with the help of other parties under privacy protection policies. Current federated learning (FL) paradigms are…

Machine Learning · Computer Science 2023-05-09 Xin-Chun Li , Yang Yang , De-Chuan Zhan

A local void in the globally Friedmann-Robertson-Walker (FRW) cosmological model is studied. The inhomogeneity is described using the Lema\^{\i}tre-Tolman-Bondi (LTB) solution with the spherically symmetric matter distribution based on the…

Astrophysics · Physics 2009-10-22 J. W. Moffat , D. C. Tatarski

This survey paper is based on a talk given at the 44th Summer Symposium in Real Analysis in Paris. This line of research was initiated by a question of Haight and Weizs\"aker concerning almost everywhere convergence properties of series of…

Classical Analysis and ODEs · Mathematics 2022-09-27 Zoltán Buczolich

Solving the Stefan problem, also referred as the heat conduction problem with phase change, is a necessary step to solve phase change problems with convection. In this article, we are interested in using the Lattice Boltzmann Method (LBM)…

Numerical Analysis · Mathematics 2025-05-20 Francky Luddens , Corentin Lothodé , Ionut Danaila

We deal with existence and uniqueness of nonnegative solutions to \begin{equation*} \left\{ \begin{array}{l} -\Delta u = f(x) \text{ in }\Omega, \frac{\partial u}{\partial \nu} + \lambda(x) u = \frac{g(x)}{u^\eta} \text{ on }…

Analysis of PDEs · Mathematics 2023-03-31 Francesco Della Pietra , Francescantonio Oliva , Sergio Segura de León

We employ recently developed approximation methods in the hybrid quantization of the Gowdy $T^3$ model with linear polarization and a massless scalar field to obtain physically interesting solutions of this inhomogeneous cosmology. More…

General Relativity and Quantum Cosmology · Physics 2015-06-22 Beatriz Elizaga Navascués , Mercedes Martín-Benito , Guillermo A. Mena Marugán

We study Density Functional Theory models for systems which are translationally invariant in some directions, such as a homogeneous 2-d slab in the 3-d space. We show how the different terms of the energy are modified and we derive reduced…

Mathematical Physics · Physics 2021-12-24 David Gontier , Salma Lahbabi , Abdallah Maichine

Different from existing federated fine-tuning (FFT) methods for foundation models, hybrid heterogeneous federated fine-tuning (HHFFT) is an under-explored scenario where clients exhibit double heterogeneity in model architectures and…

Machine Learning · Computer Science 2025-08-01 Wei Guo , Siyuan Lu , Yiqi Tong , Zhaojun Hu , Fuzhen Zhuang , Xiao Zhang , Tao Fan , Jin Dong

An approximate method based on adiabatic time dependent density functional theory (TDDFT) is presented, that allows for the description of the electron dynamics in nanoscale junctions under arbitrary time dependent external potentials. In…

Mesoscale and Nanoscale Physics · Physics 2015-05-27 Y. Wang , C. -Y. Yam , G. H. Chen , Th. Frauenheim , T. A. Niehaus

The paper focuses on a multidimensional optimization problem, which is formulated in terms of tropical mathematics and consists in minimizing a nonlinear objective function subject to linear inequality constraints. To solve the problem, we…

Optimization and Control · Mathematics 2014-05-15 Nikolai Krivulin

In this paper, we present a local $Tb$ theorem for the non-homogeneous Littlewood-Paley $g_{\lambda}^{*}$-function with non-convolution type kernels and upper power bound measure $\mu$. We show that, under the assumptions $\supp b_Q \subset…

Classical Analysis and ODEs · Mathematics 2015-07-21 Mingming Cao , Qingying Xue

This paper provides a unified framework for analyzing tensor estimation problems that allow for nonlinear observations, heteroskedastic noise, and covariate information. We study a general class of high-dimensional models where each…

Information Theory · Computer Science 2025-06-10 Riccardo Rossetti , Galen Reeves

Motivated by the dawn of precision cosmology and the wealth of forthcoming high precision and volume galaxy surveys, in this paper we study the effects of inhomogeneities on light propagation in a flat \Lambda CDM background. To this end we…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-19 Nikolai Meures , Marco Bruni

Estimation and counterfactual analysis in dynamic structural models rely on assumptions about the dynamic process of latent variables, which may be misspecified. We propose a framework to quantify the sensitivity of scalar parameters of…

Econometrics · Economics 2025-11-17 Ertian Chen

The method of choice for describing attractive quantum systems is Hartree-Fock-Bogoliubov (HFB) theory. This is a nonlinear model which allows for the description of pairing effects, the main explanation for the superconductivity of certain…

Numerical Analysis · Mathematics 2013-11-08 Mathieu Lewin , Séverine Paul

Recently, we constructed the specific solution to the second-order cosmological perturbation theory, around any Friedmann-Lemaitre-Robertson-Walker (FLRW) background filled with dust matter and a positive cosmological constant. In this…

Cosmology and Nongalactic Astrophysics · Physics 2025-10-16 Szymon Sikora , Jan J. Ostrowski