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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.

169,051 papers · 148 categories

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316192122 · May 202619922001200920182026
48 results for witness rank

New RL algorithms show model-based methods are more efficient than model-free ones in complex decision processes.

problem Efficient reinforcement learning in contextual decision processes with strategic exploration.
method Design of new model-based RL algorithms with sample complexity governed by witness rank.
result Exponential separation between model-based and model-free RL in some rich-observation settings.

OMLE combines optimism and MLE for efficient sequential decision making.

problem Efficiently solving sequential decision making problems, especially in partially observable settings.
method Combines optimism for exploration and maximum likelihood estimation for model learning.
result OMLE learns near-optimal policies for a wide range of sequential decision making problems.

Geometric framework for signed multivariate tail-dependence compatibility at various thresholds.

problem Modeling and analyzing signed multivariate tail-dependence across different thresholds.
method Developed a geometric witness framework to represent and invert signed tail families, identifying nonnegative weights and normalized masses.
result Characterization and synthesis of signed multivariate tail-dependence at finite thresholds, preserving the complete signed tail family throughout.

Proximal Mediation Analysis with Hidden Recanting Witnesses

problem Identifying path-specific effects in mediation analysis when recanting witnesses are unknown
method Proximal causal inference and semiparametric inference framework
result Developed three novel identification strategies and a semiparametric inference framework

Proposes a method to learn from multiple views with low-rank embeddings.

problem Learning from multiple views with varying correlations is challenging.
method Multi-view Locality Low-rank Embedding (MvL2E) method that uses low-rank representations and centroid-based scheme.
result MvL2E achieves comparable performance with previous methods on benchmark datasets.

A new method detects hidden driving forces in systems with multiple observables.

problem Hidden driving forces in systems with multiple observables cannot be detected by scalar statistics.
method Cross-spectral witness for hidden nonequilibrium.
result Two simultaneously observed channels retain an off-diagonal cross-spectral sector inaccessible to scalar reductions.

Robust high-dimensional data processing has witnessed an exciting development in recent years, as theoretical results have shown that it is possible using convex programming to optimize data fit to a low-rank component plus a sparse outlier component. This problem is also known as Robust PCA, and it has found applicati…

2013-06-03abs ↗pdf ↗

Survey of reinforcement learning guarantees with data constraints.

problem Guaranteeing near-optimal policies with limited data in reinforcement learning.
method Coverage-Structure-Objective (CSO) framework to decompose sample complexity results.
result Progress on PAC guarantees for reinforcement learning, covering various models and settings.

Proposes MvLPE for better multi-view representation learning.

problem Learning representations from multi-view data with varying correlations.
method Integrates multi-view data into a centroid view while maintaining low-rank reconstruction relations.
result MvLPE outperforms existing methods on benchmark datasets.

Study on deleting user data in linear regression models to maintain limited memory.

problem Deleting user data in a limited time frame for statistical models.
method Proposed FIFD-OLS and FIFD-Adaptive Ridge algorithms for low-dimensional and online settings.
result Demonstrated effectiveness of FIFD-Adaptive Ridge in maintaining statistical efficiency.

In this paper we show that certain generalizations of the CrC^r-Whitney topology, which include the Hölder-Whitney and Sobolev-Whitney topologies on smooth manifolds, satisfy the Baire property, to wit, the countable intersection of open and dense sets is dense.

2018-09-27abs ↗pdf ↗

A new method for analyzing adaptive experiments using kernel treatment effects.

problem Efficiently analyzing adaptive experiments that adjust treatment assignments based on outcomes.
method Kernel Treatment Effects (KTE) framework combining RKHS scores and witness functions.
result Effective for both mean shifts and higher-moment differences, outperforming adaptive baselines.

A new framework reduces RL sample complexity for complex MDPs.

problem Handling large state and action spaces in reinforcement learning.
method Unified model-based and model-free RL framework with ABC class, novel estimation function, and functional eluder dimension.
result OPERA algorithm achieves sample-efficient regret bounds for various MDP models.

This note shows how to transform high-probability to in-expectation guarantees in machine learning.

problem The challenge of constructing reliable machine learning models due to sampling randomness.
method Transforming high-probability to in-expectation guarantees using a witness condition for unbounded loss functions.
result A technical transformation method for generalization guarantees in machine learning.

Unified approach for multicalibration in weakly supervised learning.

problem Existing multicalibration methods require clean input-label pairs, which are unavailable in weakly supervised learning.
method Developed estimators and post-hoc correction methods for multicalibration under weak supervision.
result Unified framework for estimating and correcting multicalibration under weak supervision with finite-sample guarantees.

Paper develops efficient algorithms for zero-sum Markov games with general function classes.

problem Challenging settings in zero-sum Markov games with parameterized value functions or models.
method Developed new model-free and model-based algorithms for decoupled and coordinated settings.
result Improved sample complexity and regret bounds for various settings.

We present new, unified proofs for the cell-like, Z/p\mathbb{Z}/p-, and Q\mathbb{Q}-resolution theorems. Our arguments employ extensions that are much simpler then those used by our predecessors. The techniques allow us to solve problems involving cohomology groups by converting them into problems about homology groups…

2017-06-05abs ↗pdf ↗

Study shows how online personalization can lead to unfair models due to biased user responses.

problem Fairness issues in online personalization systems due to biased user responses.
method Formulated a regularization-based approach to mitigate biases in machine learning models.
result Demonstrated that online personalization can cause models to learn unfair behavior from biased user responses.

New methods estimate causal effects through mediators, handling confounding without strict assumptions.

problem Estimating causal effects through mediators while accounting for unmeasured confounding.
method Developed four nonparametric identification strategies using proximal confounding bridge functions, efficient influence function, and quadruply robust estimator. Proposed proximal debiased machine learning approach for high-dimensional nuisance parameters.
result Achieved n\sqrt{n}-consistency and asymptotic normality for path-specific effect estimation.

Proposes DR-ME test for interpretable distributional treatment effects.

problem Detects invisible differences in treatment effects on distributional outcomes.
method Semiparametrically efficient finite-location test using kernel witnesses and orthogonal features.
result DR-ME reveals causal-discrepancy coordinates and has noncentral chi-square local power.

We study a continuous-time version of the intermediation model of Grossman and Miller (1988). To wit, we solve for the competitive equilibrium prices at which liquidity takers' demands are absorbed by dealers with quadratic inventory costs, who can in turn gradually transfer these positions to an exogenous open market …

2018-07-22abs ↗pdf ↗

This article constructs the moduli stack of torsionfree GG-jet-structures in homotopy type theory with one monadic modality. This yields a construction of this moduli stack for any \infty-topos equipped with any stable factorization systems. In the intended applications of this theory, the factorization systems are …

2018-06-15abs ↗pdf ↗

Given a closed simply connected manifold MM of dimension 2n62n\ge6, we compare the ring of characteristic classes of smooth oriented bundles with fibre MM to the analogous ring resulting from replacing MM by the connected sum MΣM\sharpΣ with an exotic sphere ΣΣ. We show that, after inverting the order of ΣΣ in the …

2018-02-07abs ↗pdf ↗

A new method uses Hermite polynomials to improve machine learning models.

problem Improving the accuracy of machine learning models using non-positive kernels.
method Using multi-variate Hermite polynomials and a permutation test to approximate measures and classify data.
result The witness function method can reliably identify in-class vs out-of-class regions.

The study shows that several properties are not profinite invariants.

problem Determining which properties are profinite invariants.
method Combining Rips constructions and iterated group-theoretic Dehn filling on hyperbolic virtually special groups.
result Several properties (stable commutator length, quasimorphisms, property NL, property FW_\infty, property FA, and non-abelian free subgroups) are not profinite invariants.

Transformer models improve query-document retrieval efficiency and accuracy.

problem Efficiently retrieve relevant documents from large corpora for query matching.
method Designed paragraph-level pre-training tasks to optimize embedding-based Transformer models.
result Transformer models significantly outperform BM-25 and non-Transformer embedding models.

A framework for analyzing financial systems under scenario constraints.

problem Quantifying worst-case and best-case performance in financial systems.
method Quantitative automata-based framework integrating event history automata and weighted finance finite automata.
result Exact calculation of upper and lower payoff bounds with interpretable witness event histories.