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arXiv research

A locally-built, LLM-digested index of recent arXiv papers in quant finance, geometry/topology, and statistical ML — keyword search served straight from SQLite on this machine.

168,657 papers · 148 categories

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162324486648 · Jun 202019922001200920172026
48 results for Quasianalytic functions

A systematic geometric theory for the ultradifferentiable (non-quasianalytic and quasianalytic) wavefront set similar to the well-known theory in the classic smooth and analytic setting is developed. In particular an analogue of Bony's Theorem and the invariance of the ultradifferentiable wavefront set under diffeomorp…

2018-05-29abs ↗pdf ↗

Quantifies polynomial approximation rates for smooth functions under various distributions.

problem Approximating smooth functions with polynomials under different distributional constraints.
method Develops a quantitative analogue of Carleman's theorem using complex analysis.
result Establishes superexponential rates of approximation for certain function classes over general distributions.

We construct examples of CC^\infty smooth submanifolds in Cn{\Bbb C}^n and Rn{\Bbb R}^n of codimension 2 and 1, which intersect every complex, respectively real, analytic curve in a discrete set. The examples are realized either as compact tori or as properly imbedded Euclidean spaces, and are the graphs of quasianaly…

2004-02-23abs ↗pdf ↗

Uniform proof for ultradifferentiability in various classes and dimensions.

problem Generalizing ultradifferentiability conditions to multidimensional cases and infinite dimensional spaces.
method Uniform proof approach that works in all cases and dimensions, including infinite dimensional Banach spaces and convenient vector spaces.
result Characterization of ultradifferentiability for general analytic germs and functions.

By an influential theorem of Boman, a function ff on an open set UU in Rd\mathbb R^d is smooth (C\mathcal C^\infty) if and only if it is arc-smooth, i.e., fcf\circ c is smooth for every smooth curve c:RUc : \mathbb R \to U. In this paper we investigate the validity of this result on closed sets. Our main focus is on s…

2018-01-25abs ↗pdf ↗

We prove the exponential law A(E×F,G)A(E,A(F,G))\mathcal A(E \times F, G) \cong \mathcal A(E,\mathcal A(F,G)) (bornological isomorphism) for the following classes A\mathcal A of test functions: B\mathcal B (globally bounded derivatives), W,pW^{\infty,p} (globally pp-integrable derivatives), S\mathcal S (Schwartz space), D\mathcal D

2014-11-03abs ↗pdf ↗

Develops methods for selecting and estimating smooth functional coefficients in high-dimensional multivariate functional data.

problem Functional predictor selection and estimation of smooth functional coefficients in high-dimensional multivariate functional data.
method Functional group-sparse regression methods in a generic Hilbert space of infinite dimension.
result Consistency of estimation and selection (oracle property) under infinite-dimensional Hilbert spaces.

FFBO optimizes functions as inputs and outputs, improving on existing BO methods.

problem Optimizing functions as both inputs and outputs in complex systems.
method Function-on-function Gaussian process (FFGP) model with a separable operator-valued kernel, scalar upper confidence bound (UCB) acquisition function, and scalable functional gradient ascent algorithm (FGA).
result FFBO outperforms existing methods in synthetic and real-world data.

Chirped sinosoids and interferometric phase plots are functions that are not periodic, but are the composition of a smooth function and a periodic function. These functions functions factor into a pair of maps: from their domain to a circle, and from a circle to their codomain. One can easily imagine replacing the circ…

2015-01-25abs ↗pdf ↗

The Fridman function is bounded by the injectivity radius for certain hyperbolic manifolds.

problem Bounding the Fridman function for hyperbolic manifolds.
method Analyzing the relationship between the Fridman function and the injectivity radius function.
result The Fridman function is bounded above by the injectivity radius function for certain hyperbolic manifolds.

The paper proves isoparametric functions on Finsler space forms under specific conditions.

problem Understanding isoparametric functions in Finsler space forms.
method Proving transnormal functions as isoparametric functions and constructing global and local isoparametric functions using the distance function.
result Generalization of Theorem B to Finsler space forms.

Paper introduces a nonparametric functional graphical model for random functions.

problem Estimating probabilistic conditional independence in functional graphical models.
method Functional sufficient dimension reduction to relax Gaussian or copula Gaussian assumptions.
result Enhances estimation accuracy and retains probabilistic conditional independence.

Robustifies elicitable functionals to handle small distribution misspecifications.

problem Determining uniquely optimal forecasts under distributional misspecification.
method Integrates statistical robustness into elicitable functionals using Kullback-Leibler divergence.
result Robust elicitable functionals admit unique solutions at the boundary of uncertainty regions.

The paper characterizes strong Hamel functions using symmetries and proves their preservation properties.

problem Characterizing strong Hamel functions and their symmetries in Finsler spaces.
method Analyzing geodesic spray, strong dual symmetries, and strong dynamical symmetries.
result Strong Hamel functions can be characterized in terms of strong dual symmetries and strong dynamical symmetries.

Two new methods improve forecasting of functional time series data.

problem Forecasting of functional time-dependent data.
method Functional Singular Spectrum Analysis (FSFA) based forecasting methods.
result Our methods outperform existing algorithms for periodic stochastic processes.

Study stabilizers of smooth functions on surfaces, focusing on Morse-Bott functions.

problem Understanding the homotopy type of stabilizers of smooth functions on surfaces.
method Analyzing the homotopy properties of stabilizers for a specific class of smooth functions.
result The homotopy type of the connected component of the identity map of the stabilizer is completely described for Morse-Bott functions.

The paper connects convex functions to p-subharmonic functions and proves their equivalence.

problem Understanding the relationship between convex functions and p-subharmonic functions.
method Average principle, variational methods, and PDE techniques.
result Convex functions on R^n are p-subharmonic for every p > 1.

A new deep neural network tackles nonlinear functional regression with improved dimensionality reduction.

problem Nonlinear functional regression in infinite-dimensional functional data analysis.
method Functional deep neural network with adaptive kernel embedding and projection steps.
result Explicit rates of approximating nonlinear smooth functionals are derived, and the network is shown to be effective in both simulated and real datasets.

New model for network analysis using functional data.

problem Existing network models treat nodes as functions, but this paper introduces functional edges.
method Transform adjacency matrix into functional adjacency tensor, apply Tucker decomposition, regularize basis matrices, and solve tensor completion problem.
result The model effectively captures community structure and handles irregular functional edge data.

The study finds a special type of smooth function on connected sums of manifolds.

problem Finding smooth functions that are Morse on preimages of non-extrema values.
method Investigates internally Morse (I-Morse) and neat with respect to Reeb graph (N-Reeb) functions.
result Constructs an IN-Morse-Reeb function on a connected sum of given manifolds.

NeuTSFlow models continuous functions behind time series forecasting.

problem Forecasting treats time series as discrete sequences, ignoring their continuous nature.
method NeuTSFlow uses Neural Operators to learn the transition between historical and future function families.
result NeuTSFlow outperforms traditional methods in forecasting accuracy and robustness.

New spectral functionals for Dirac operators with inner fluctuations computed.

problem Spectral functionals and Dirac operators with inner fluctuations.
method Extension of spectral functionals for Dirac operators with inner fluctuations.
result Computed spectral Einstein functional for Dirac operator with inner fluctuations on even-dimensional spin manifolds.

Regularizers change the geometric properties of loss functions in neural networks.

problem Understanding how different regularizers affect the geometric properties of loss functions in neural networks.
method Examined several regularizers, including weight decay, to determine if the regularized loss function becomes Morse.
result For certain regularizers, the regularized loss function becomes Morse, indicating a change in geometric properties.

Proposes an L1-regularized functional SVM for binary classification with functional covariates.

problem Binary classification with multivariate functional covariates.
method L1-regularized functional support vector machine (SVM) with an accompanying algorithm.
result The proposed classifier performs well in prediction and feature selection.

In this paper we propose and study a family of sparsity-inducing penalty functions. Since the penalty functions are related to the kinetic energy in special relativity, we call them \emph{kinetic energy plus} (KEP) functions. We construct the KEP function by using the concave conjugate of a χ2χ^2-distance function and …

2013-07-22abs ↗pdf ↗

The paper calculates asymptotic expansions for specific types of oscillatory integrals.

problem Analyzing oscillatory integrals with complex phase functions.
method Using asymptotic expansions of simpler phase functions to derive results for more complex cases.
result Explicit computation of coefficients in asymptotic expansions for certain integrals.

Defines 'nowhere coexpanding functions' and studies their fixed points.

problem Understanding fixed points of nowhere coexpanding functions.
method Defines and studies C1C^1 nowhere coexpanding functions, including C3C^3 functions with non-positive Schwarzian derivative.
result Establishes results on the number and nature of fixed points, generalizing Singer's result.

Proposes a method to estimate functional graphical models from multivariate random functions.

problem Estimating conditional independence structure of multivariate random functions.
method Neighborhood selection approach combining function-on-function regression and graph recovery.
result Statistical consistency of the method in high-dimensional settings.

This paper optimizes Bayesian acquisition functions in Gaussian Processes for better optimization.

problem Improving the efficiency of Bayesian optimization methods.
method Analysis of different acquisition functions and optimizers for optimizing Bayesian acquisition functions.
result Optimization of acquisition functions leads to faster and more accurate sampling points.

The paper uses MDM theory to analyze multifiltering functions on simplicial complexes.

problem Understanding multifiltering functions through discrete Morse theory.
method Applying multiparameter discrete Morse theory to vector-valued multifiltering functions.
result Any multifiltering function can be approximated by a compatible MDM function.