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.

168,695 papers · 148 categories

Trend · papers per month

128256384512 · Jun 202019922001200920172026
48 results for stochastic availability

We quantify content availability and user discovery opportunities in recommender systems.

problem Determining the maximum probability of recommending content to users.
method Stochastic reachability to compute upper bounds on recommendation likelihood.
result Reachability metrics can detect biases and diagnose user discovery limitations.

New algorithms for approximating stochastic processes efficiently.

problem Finding accurate finite approximations for stochastic processes.
method Develops new algorithms and fast implementations for approximating stochastic processes.
result Efficient approximations for stochastic processes can be found.

New algorithms handle unpredictable actions in sequential learning.

problem Learning with unreliable composite actions in online optimization.
method Follow-The-Perturbed-Leader method with Counting Asleep Times loss estimation.
result Significant improvement in performance guarantees for sleeping bandit problem.

The Markov decision process (MDP) formulation used to model many real-world sequential decision making problems does not efficiently capture the setting where the set of available decisions (actions) at each time step is stochastic. Recently, the stochastic action set Markov decision process (SAS-MDP) formulation has b…

2019-06-05abs ↗pdf ↗

AdaSub optimizes with second-order info in low-dims subspace.

problem Efficiently use second-order optimization methods with low computational cost.
method Adaptive subspace selection for second-order optimization.
result AdaSub outperforms other stochastic optimizers in time and iterations.

Method extracts governing laws from non-Gaussian stochastic systems data.

problem Modeling complex dynamics with non-Gaussian Lévy noise.
method Data-driven method to extract stochastic dynamical systems from noisy data.
result Established a theoretical framework and numerical algorithm to compute Lévy jump measure, drift, and diffusion.

Method learns dynamics of slow variables from stochastic data.

problem Modeling unknown multiscale stochastic systems with limited data.
method Data-driven approach to learn effective dynamics from bursts of observation data.
result Generative model accurately captures effective dynamics of slow variables.

ProxSPS improves on SPS for regularization tasks, offering better stability and performance.

problem Handling regularization terms in adaptive step size schemes for stochastic gradient descent.
method Developed a proximal variant of the stochastic Polyak step size (SPS) scheme.
result ProxSPS is easier to tune and more stable with regularization, and performs well in image classification tasks.

Method solves complex optimization problems with high probability bounds.

problem Nonlinear equality constrained stochastic optimization problems.
method Step-search sequential quadratic programming method.
result High-probability bound on iteration complexity for first-order stationarity.

Stochastic optimization problems often involve the expectation in its objective. When risk is incorporated in the problem description as well, then risk measures have to be involved in addition to quantify the acceptable risk, often in the objective. For this purpose it is important to have an adjusted, adapted and eff…

2012-09-17abs ↗pdf ↗

New algorithm improves source separation with multi-trial supervision.

problem Non-convex optimization and interpretability of independent components.
method Proximal gradient-type algorithm in invertible matrices with backpropagation for joint learning.
result Increased success rate of non-convex optimization and improved interpretability.

New algorithms for IV regression with streaming data, avoiding matrix inversions.

problem Instrumental variable regression with streaming data.
method Viewing IV regression as a stochastic optimization problem, developing algorithms that avoid matrix inversions and mini-batches.
result Rates of convergence of order O(logT/T)\mathcal{O}(\log T/T) and O(1/T1ι)\mathcal{O}(1/T^{1-ι}) for linear models.

Contrary to the situation with stochastic gradient descent, we argue that when using stochastic methods with variance reduction, such as SDCA, SAG or SVRG, as well as their variants, it could be beneficial to reuse previously used samples instead of fresh samples, even when fresh samples are available. We demonstrate t…

2016-02-05abs ↗pdf ↗

In this letter, we introduce a distributed Nesterov method, termed as ABN\mathcal{ABN}, that does not require doubly-stochastic weight matrices. Instead, the implementation is based on a simultaneous application of both row- and column-stochastic weights that makes this method applicable to arbitrary (strongly-connected…

2019-01-21abs ↗pdf ↗

This work tackles resource allocation in asynchronous and stochastic systems.

problem Distributed resource allocation in asynchronous and stochastic settings.
method Approximate stochastic primal-dual approach with asynchronous updates.
result The Asynchronous stochastic Primal-Dual (Asyn-PD) algorithm converges to the saddle point solution at a rate of O(1/t)O(1/t).

Extends XVA valuation under stochastic volatility, characterizing value processes via mild solutions.

problem Valuation of contingent claims in presence of default, collateral, and funding under stochastic volatility.
method Characterizes pre-default value processes via mild solutions to parabolic semilinear PDEs under stochastic volatility.
result Characterizes pre-default value processes via mild solutions to parabolic semilinear PDEs under stochastic volatility, providing sufficient conditions for existence and uniqueness.

Apollo improves nonconvex stochastic optimization efficiency.

problem Nonconvex stochastic optimization challenges.
method Adaptive parameter-wise diagonal quasi-Newton method approximating Hessian.
result Significant improvements in convergence speed and generalization over SGD and Adam.

New method improves online covariance estimation for SGD.

problem Improving online covariance estimation for SGD.
method Proposes a de-biased covariance estimator that eliminates second-order derivatives.
result Achieves a convergence rate of n(α1)/2lognn^{(α-1)/2} \sqrt{\log n}, outperforming existing methods.

In deterministic optimization, line searches are a standard tool ensuring stability and efficiency. Where only stochastic gradients are available, no direct equivalent has so far been formulated, because uncertain gradients do not allow for a strict sequence of decisions collapsing the search space. We construct a prob…

2017-03-29abs ↗pdf ↗

In deterministic optimization, line searches are a standard tool ensuring stability and efficiency. Where only stochastic gradients are available, no direct equivalent has so far been formulated, because uncertain gradients do not allow for a strict sequence of decisions collapsing the search space. We construct a prob…

2015-02-10abs ↗pdf ↗

New method transforms complex stochastic equations into simpler ones for efficient simulation.

problem Efficient simulation of complex path-dependent stochastic processes.
method Transforms Volterra-type SDEs into standard diffusion processes using convolution kernels.
result Proposes a numerical simulation scheme with a strong convergence rate of 1/2.

This paper develops a communication-efficient algorithm to solve the stochastic optimization problem defined over a distributed network, aiming at reducing the burdensome communication in applications such as distributed machine learning.Different from the existing works based on quantization and sparsification, we int…

2019-09-09abs ↗pdf ↗

The chapter compares Gaussian process models for stochastic simulators with varying noise.

problem Modeling stochastic simulators with varying noise.
method Various Gaussian process models are compared, including input varying noise variance, non-Gaussian noise, and quantile modeling.
result Sequential design procedures are adapted for these models.

In this paper we study stochastic quasi-Newton methods for nonconvex stochastic optimization, where we assume that noisy information about the gradients of the objective function is available via a stochastic first-order oracle (SFO). We propose a general framework for such methods, for which we prove almost sure conve…

2016-07-05abs ↗pdf ↗

We introduce a multivariate stochastic volatility model for asset returns that imposes no restrictions to the structure of the volatility matrix and treats all its elements as functions of latent stochastic processes. When the number of assets is prohibitively large, we propose a factor multivariate stochastic volatili…

2015-10-18abs ↗pdf ↗

Estimates and optimizes UBSR risk in recursive settings.

problem Estimating and optimizing UBSR risk in a recursive setting with one-at-a-time samples.
method Casts UBSR as a root finding problem, uses stochastic approximation and gradient descent.
result Derives non-asymptotic bounds on estimation and optimization errors.

Designs a single policy for collecting data to train near-optimal policies.

problem Engineering overhead in deploying minimax procedures for stochastic linear contextual bandits.
method Designs a single stochastic policy to collect data from which a near-optimal policy can be extracted.
result The designed policy can collect data from which a near-optimal policy can be extracted.

New algorithm finds approximate stationary points in non-convex optimization.

problem Finding approximate stationary points in non-convex stochastic optimization.
method Design of an algorithm using O(ε3)O(ε^{-3}) stochastic gradient and Hessian-vector products.
result Optimal rate of O(ε3)O(ε^{-3}) for finding εε-approximate stationary points, matching lower bounds.

Deep neural networks have had an enormous impact on image analysis. State-of-the-art training methods, based on weight decay and DropOut, result in impressive performance when a very large training set is available. However, they tend to have large problems overfitting to small data sets. Indeed, the available regulari…

2016-05-30abs ↗pdf ↗

Stochastic blockmodels and variants thereof are among the most widely used approaches to community detection for social networks and relational data. A stochastic blockmodel partitions the nodes of a network into disjoint sets, called communities. The approach is inherently related to clustering with mixture models; an…

2014-12-04abs ↗pdf ↗

A new method avoids noise amplification when subtracting or dividing stochastic signals.

problem Noise amplification when subtracting or dividing stochastic signals.
method Normalizing flows to approximate the distribution of the signal of interest.
result Normalizing flows can generate an approximation of the probability distribution over the signal of interest, avoiding subtraction or division.

In this work we are concerned with valuing optionalities associated to invest or to delay investment in a project when the available information provided to the manager comes from simulated data of cash flows under historical (or subjective) measure in a possibly incomplete market. Our approach is suitable also to inco…

2015-09-11abs ↗pdf ↗

The paper identifies network bottlenecks using minimax paths in stochastic networks.

problem Identifying bottlenecks in networks with stochastic weights.
method Modeling as combinatorial semi-bandit problem, applying combinatorial Thompson Sampling, and approximating the original objective due to computational intractability.
result Established an upper bound on Bayesian regret and evaluated Thompson Sampling performance on real-world networks.