Research
On-device research index

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.

168,694 papers · 148 categories

Trend · papers per month

51102152203 · May 202619922001200920172026
48 results for concave operators

Study estimates eigenvalues for concave Hessian operators on convex domains.

problem Estimating eigenvalues for concave elliptic Hessian operators.
method Investigates Dirichlet eigenvalue problem for a broad class of concave elliptic Hessian operators.
result Existence and properties of the first nonzero eigenvalue and eigenfunction.

Paper introduces \ell-DER for regression tasks using morphological operators and convex-concave procedure.

problem Developing a universal approximator for regression tasks.
method Introduces \ell-DER model, trains it using a convex-concave procedure (CCP) to minimize least-squares.
result Outperforms other hybrid morphological models and state-of-the-art approaches.

Study concavity of solutions to elliptic equations under conformal deformations.

problem Establish concavity estimates for the principle eigenfunction of weighted Schrödinger operators.
method Analyzing the Dirichlet problem for the weighted Schrödinger operator \[-Δu + Vu = λρu\] with conformal connections.
result Partial resolution of Nguyen's conjecture on fundamental gap of horoconvex domains and power convexity estimate for solutions in spherical geometry.

The study improves fundamental gap estimates for surfaces with non-constant positive curvature.

problem Estimating the fundamental gap for surfaces with non-constant positive curvature.
method Using a two-point maximum principle, the study establishes log-concavity and fundamental gap estimates.
result Corresponding log-concavity and fundamental gap estimates for surfaces with non-constant positive curvature are derived.

Algorithm samples from composite log-concave distributions using gradient evaluations and restricted Gaussian oracles.

problem Sampling from composite log-concave distributions with limited gradient evaluations.
method Proximal gradient algorithm with RGO for gg and strong/strongly convex conditions for ff.
result Achieves εε error in total variation distance in O~(κdlog4(1/ε))\widetilde{\mathcal O}(κ\sqrt d \log^4(1/ε)) iterations.

The paper proves extension theorems for complex manifolds with Levi qq-concave domains.

problem Holomorphic extension theorems for complex manifolds with Levi qq-concave domains.
method The proof relies on holomorphic Morse inequalities, the Kohn-Rossi extension theorem, and a general Nakano-Griffiths inequality.
result Holomorphic extension theorems for (0,)(0,\ell)-forms on Levi qq-concave domains.

Study on critical Lagrangian phase singularities in mean curvature flow.

problem Analyzing singularities in the Lagrangian mean curvature flow at the critical phase.
method Developed new method to prove C2,αC^{2,\alpha} estimates by using concave operators.
result Established interior estimates for critical Lagrangian phase singularities.

Stein's method for measuring convergence to a continuous target distribution relies on an operator characterizing the target and Stein factor bounds on the solutions of an associated differential equation. While such operators and bounds are readily available for a diversity of univariate targets, few multivariate targ…

2016-11-21abs ↗pdf ↗

Study shows splitting schemes can approximate WFR flows faster than the exact flow.

problem Improving sampling efficiency in Wasserstein-Fisher-Rao gradient flows.
method Investigates operator splitting techniques to numerically approximate WFR flows.
result A judicious choice of step size and operator ordering can lead to faster convergence of split schemes to the target distribution.

A new algorithm reduces online exp-concave optimization runtime.

problem Minimizing regret in online learning with exponentially concave losses.
method LightONS, a variant of Online Newton Step (ONS), reduces runtime to O(d2T+dωTlogT)O(d^2 T + d^ω\sqrt{T \log T}).
result Optimal regret with reduced runtime to O(d2T+dωTlogT)O(d^2 T + d^ω\sqrt{T \log T}).

We study the Dirichlet problem for the Lagrangian phase operator, in both the real and complex setting. Our main result states that if ΩΩ is a compact domain in Rn\mathbb{R}^{n} or Cn\mathbb{C}^n, then there exists a solution to the Dirichlet problem with right-hand side h(x)h(x) satisfying h(x)>(n2)π2|h(x)| > (n-2)\fracπ{2} and…

2016-07-25abs ↗pdf ↗

A new sampling method reduces computational cost for high-dimensional log-concave distributions.

problem High computational cost of ULMC in high dimensions.
method Random Coordinate ULMC (RC-ULMC) selects a single coordinate per iteration.
result RC-ULMC is cheaper than classical ULMC, especially in highly skewed and high-dimensional problems.

Study proves estimate for Hessian quotient equations on 2D Riemannian manifolds.

problem Problems posed by Delanoë and Urbas related to Hessian quotient equations.
method Maximum principle argument and new test function introduced to prove estimate.
result Unobstructed second order a priori estimate for real Hessian quotient equation in 2D.

Solves curvature problems on manifolds with negative curvature.

problem Prescribed curvature problems on closed manifolds with negative curvature.
method Investigates fully nonlinear prescribed curvature problems for modified Schouten tensor on closed Riemannian manifolds with negative curvature.
result Proves solvability of curvature problems under certain conditions.

New algorithms solve monotone inclusions and convex-concave minimax problems.

problem Solving maximally monotone equations and inclusions.
method Developed new accelerated algorithms based on Halpern-type fixed-point iteration and Popov's past extra-gradient method.
result Achieved O(1/k)\mathcal{O}(1/k) convergence rates for various problems.

This paper approaches the definition and properties of dynamic convex risk measures through the notion of a family of concave valuation operators satisfying certain simple and credible axioms. Exploring these in the simplest context of a finite time set and finite sample space, we find natural risk-transfer and time-co…

2007-09-03abs ↗pdf ↗

This paper tackles bandit optimization with a new pairwise comparison oracle for unknown strongly concave functions.

problem Maximizing an unknown strongly concave function over T periods with a biased pairwise comparison oracle.
method Introduced a discretization technique and local polynomial approximation to relate the problem to linear bandits. Developed a tournament successive elimination technique to localize the discretized cell and run LinUCB algorithm on cells.
result Established optimal regret bounds and improved state-of-the-art results in operations management problems.

Study improves sampling from non-log-concave distributions using Fisher information.

problem Sampling from non-log-concave distributions with high Fisher information guarantees.
method Proximal sampler with RGO implementation, leveraging log-concave sampling results.
result Improved complexity guarantee in relative Fisher information for non-log-concave sampling.

Proposes a neural network framework for feature selection in high-dimensional settings.

problem Challenges in feature selection and non-linear function estimation in high-dimensional settings.
method Sparse-input neural networks using group concave regularization.
result Establishes finite-sample guarantees for variable selection consistency and prediction accuracy.

Established concavity principle for curved spaces.

problem Solving equations on curved spaces with nonnegative curvature.
method Applied concavity principle to elliptic and parabolic equations on locally symmetric spaces with nonnegative curvature.
result First general concavity principle on spaces with non-constant sectional curvature.

Establishes log-concavity estimates for convex domains' first Dirichlet eigenfunctions.

problem Quantifying the Hessian of log-concave eigenfunctions on convex domains.
method Analyzes log-concavity properties of the first Dirichlet eigenfunction on convex domains.
result Obtains quantitative estimates for the Hessian of logu\log u.

New saddle network architectures preserve convex-concave geometry in optimization problems.

problem Optimization models with convex x and concave y components.
method Structured separable decomposition and saddle network architectures.
result Proven one-dimensional approximation theorem and high accuracy on various test functions.

We present a simple connection between differential Harnack inequalities for hypersurface flows and natural concavity properties of their time-of-arrival functions. We prove these concavity properties directly for a large class of flows by applying a concavity maximum principle argument to the corresponding level set f…

2019-12-13abs ↗pdf ↗

We define a class of L-convex-concave subsets of RPn\Bbb{R}P^n, where L is a projective subspace of dimension l in RPn\Bbb{R}P^n. These are sets whose sections by any (l+1)-dimensional space L' containing L are convex and concavely depend on L'. We introduce an L-duality for these sets, and prove that the L-dual to an L-…

2002-03-19abs ↗pdf ↗

We study martingale inequalities from an analytic point of view and show that a general martingale inequality can be reduced to a pair of deterministic inequalities in a small number of variables. More precisely, the optimal bound in the martingale inequality is determined by a fixed point of a simple nonlinear operato…

2014-01-19abs ↗pdf ↗