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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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2605217811,041 · Jun 202019922001200920172026
48 results for state variable processes

The paper tackles reinforcement learning with exogenous variables and rewards.

problem Exogenous state variables and rewards slow reinforcement learning by introducing uncontrolled variation.
method Formalizes exogenous state variables and rewards, decomposes MDP into exogenous and endogenous components, and introduces algorithms to discover these components.
result Optimal policies for the endogenous MDP are also optimal for the original MDP, but the endogenous MDP is easier to solve due to reduced variance.

New model captures state-dependent variability in partially observed systems.

problem Structured stochasticity not captured by constant-variance models.
method State-coupled stochastic volatility framework with particle expectation-maximization.
result Model consistently reduces recovery bias under partial observation.

SEEK algorithm selects minimal state in reinforcement learning for better policy learning.

problem Challenges in obtaining a state representation that is parsimonious and satisfies the Markov property.
method SEEK algorithm estimates the minimal sufficient state in reinforcement learning.
result The SEEK algorithm achieves selection consistency in large samples.

Investigates fund separations and stability for long-term optimal investments.

problem Optimizing long-term investments in an incomplete market with risky and safe assets.
method Analyzes three market models with different state variable processes to find optimal portfolios and prove convergence stability.
result Dynamic optimal portfolios converge to static portfolios over time, with vanishing sensitivities in the long run.

Current economic theories miss most of economic dynamics.

problem Accuracy of economic theories and policies depend on economic variables and processes.
method Identify and analyze overlooked economic variables and processes.
result Many economic variables and processes not accounted for in current theories.

New method for efficient Bayesian inference in GPSSMs.

problem Challenges in inference for Gaussian process state-space models.
method Free-form variational inference with stochastic gradient Hamiltonian Monte Carlo.
result Our method learns transition dynamics and latent states more accurately than competing methods.

Natural Language Processing models help encode categorical process inputs.

problem Encoding categorical variables in industrial process modeling.
method Using NLP models for categorical variable encoding, combined with dimensionality reduction.
result Meaningful embeddings of categorical variables improve feature importance.

Sparse GPs improved with nearest neighbor inducing variables.

problem Sparse GPs struggle with large numbers of inducing variables.
method Introduced a hierarchical prior for inducing variables and used nearest neighbor information for sparsity.
result Significant computational gains compared to standard sparse GPs.

Enhances inference of spreading processes using neural-network priors.

problem Estimating initial states of graph processes from partial observations.
method Bayesian framework with single-layer perceptron neural network for initial states; hybrid BP-AMP algorithm.
result Model exhibits first-order phase transitions, creating a statistical-to-computational gap.

A multi-task GP model tracks time-varying transition probabilities between two states.

problem Tracking time-varying transition probabilities between 'moves' and 'pauses' states.
method Kernel-based multi-task Gaussian Process model with time-variability and constraints.
result Enforces constraints while learning transition probabilities.

Model financial markets using information theory with a single parameter.

problem Capture the complexity of financial markets with a simple model.
method Derive an idealized model based on four information-theoretic assumptions, minimizing surprisal and divergence.
result The model uses squared radial Ornstein-Uhlenbeck processes for state variables and their sums.

SiBBlInGS discovers interpretable building blocks across states in multi-way data.

problem Identifying interpretable units (Building Blocks) in multi-state, multi-way data.
method Graph-based dictionary learning approach for sparse BBs and temporal traces.
result Captures per-trial variability and state-specific vs. state-invariant components.

For recurrent neural networks trained on time series with target and exogenous variables, in addition to accurate prediction, it is also desired to provide interpretable insights into the data. In this paper, we explore the structure of LSTM recurrent neural networks to learn variable-wise hidden states, with the aim t…

2019-05-28abs ↗pdf ↗

We extend Neural Processes (NPs) to sequential data through Recurrent NPs or RNPs, a family of conditional state space models. RNPs model the state space with Neural Processes. Given time series observed on fast real-world time scales but containing slow long-term variabilities, RNPs may derive appropriate slow latent …

2019-06-13abs ↗pdf ↗

We investigate the joint description of the interest-rate term stuctures of Italy and an AAA-rated European country by mean of a --here proposed-- correlated CIR-like bivariate model where one of the state variables is interpreted as a benchmark risk-free rate and the other as a credit spread. The model is constructed …

2008-07-24abs ↗pdf ↗

Novel framework for contextual anomaly detection models uncertainty.

problem Identifying anomalies in target variables influenced by contextual variables.
method Normalcy score (NS) framework using heteroscedastic Gaussian process regression.
result NS outperforms state-of-the-art methods in detection accuracy and interpretability.

In complex processes, various events can happen in different sequences. The prediction of the next event given an a-priori process state is of importance in such processes. Recent methods have proposed deep learning techniques such as recurrent neural networks, developed on raw event logs, to predict the next event fro…

2019-03-12abs ↗pdf ↗

Bayesian non-linear latent variable modeling for complex data.

problem Inference for GPLVMs is computationally limited and often leads to overfitting or underestimates uncertainty.
method Approximate Gaussian process mappings with random Fourier features for MCMC inference.
result Generalized RFLVMs perform well on various data types and applications.

Study proposes a new model for joint survival annuity valuation.

problem Valuation of joint survival annuities and options.
method Linear-rational Wishart mortality model based on stochastic matrix affine process.
result Derives closed-form expression for joint survival annuity and option.

The paper simplifies multi-agent RL dynamics in finite-state Markov games using homogenization.

problem Approximating complex multi-agent reinforcement learning dynamics in finite-state Markov games.
method Rescaling learning process by reducing learning rate and increasing update frequency, proving convergence to an ODE.
result The rescaled process converges to an ODE that approximates the agent's learning dynamics.

Modified asymmetric hidden Markov models for time series with autoregressive components.

problem Dynamic relationships between variables in time series data.
method Introducing an asymmetric autoregressive component to recent asymmetric hidden Markov models.
result The model can choose the optimal autoregressive order for better likelihood.

Bayesian approach improves performance in Gaussian process models.

problem Scalable posterior estimation in Gaussian process models.
method Revisiting variational inference techniques with Bayesian treatment of inducing variables and hyper-parameters.
result State-of-the-art performance demonstrated across various regression and classification problems.

New method for evaluating policies in complex decision-making models with hidden variables.

problem Evaluating policies in partially observable Markov decision processes with hidden confounders.
method Introduces novel identification methods and minimax estimation techniques for linking target policy's value and observed data distribution.
result Proposes three estimators for off-policy evaluation in POMDPs with latent confounders, demonstrating their effectiveness through nonasymptotic and asymptotic analysis.

In this paper we study convex stochastic search problems where a noisy objective function value is observed after a decision is made. There are many stochastic search problems whose behavior depends on an exogenous state variable which affects the shape of the objective function. Currently, there is no general purpose …

2010-06-22abs ↗pdf ↗

A new algorithm uses IVs to learn optimal policies from observational data.

problem Learning optimal policies from unobserved variable confounded data.
method IV-aided Value Iteration (IVVI) algorithm based on conditional moment restrictions.
result First provably efficient algorithm for instrument-aided offline RL.

The paper analyzes optimal consumption with past spending maximum as a reference.

problem Optimal consumption with past spending maximum as a reference.
method Path-dependent exponential utility, Hamilton-Jacobi-Bellman (HJB) equation, dual transform, smooth-fit principle.
result Closed-form solutions for optimal investment and consumption strategies in each region.

Study uses a bivariate model to price crude oil futures.

problem Pricing crude oil futures using latent factors and state-space models.
method Modelled short and long term factors as OU processes, estimated using Kalman Filter and maximised Gaussian likelihood.
result Successfully estimated model parameters and factors from WTI Crude Oil NYMEX futures data.

Continuous time Bayesian networks (CTBNs) describe structured stochastic processes with finitely many states that evolve over continuous time. A CTBN is a directed (possibly cyclic) dependency graph over a set of variables, each of which represents a finite state continuous time Markov process whose transition model is…

2012-10-19abs ↗pdf ↗

The Gaussian process latent variable model (GP-LVM) is a popular approach to non-linear probabilistic dimensionality reduction. One design choice for the model is the number of latent variables. We present a spike and slab prior for the GP-LVM and propose an efficient variational inference procedure that gives a lower …

2015-05-10abs ↗pdf ↗

Develops a new method for nonlinear dimension reduction using random features.

problem Statistical challenges in generalizing Gaussian process-based latent variable models to non-Gaussian data.
method Random feature latent variable models (RFLVMs) that approximate nonlinear relationships with linear functions of random features.
result RFLVMs produce comparable results to state-of-the-art methods on various data types.

Latent force models (LFMs) are hybrid models combining mechanistic principles with non-parametric components. In this article, we shall show how LFMs can be equivalently formulated and solved using the state variable approach. We shall also show how the Gaussian process prior used in LFMs can be equivalently formulated…

2012-02-14abs ↗pdf ↗

Enhances Gaussian process models for handling variable error variances and multiple responses.

problem Limited ability of Gaussian process models to capture abrupt changes and heteroscedastic errors.
method Introduces a novel heteroscedastic Gaussian process (HeGP) framework coupled with variational inference and EM algorithm.
result Effective modeling of multivariate responses with varying error variances.

We propose a nonparametric procedure to achieve fast inference in generative graphical models when the number of latent states is very large. The approach is based on iterative latent variable preselection, where we alternate between learning a 'selection function' to reveal the relevant latent variables, and use this …

2014-12-10abs ↗pdf ↗

The paper introduces a new volatility model for state heterogeneous financial markets using high-frequency data.

problem State heterogeneity in financial volatility processes.
method Developed a state heterogeneous GARCH-Ito (SG-Ito) model based on continuous Ito diffusion process.
result Empirical studies reveal various state heterogeneities in S&P 500 index volatility.

Quantum Process Tomography (QPT) methods aim at identifying, i.e. estimating, a given quantum process. QPT is a major quantum information processing tool, since it especially allows one to characterize the actual behavior of quantum gates, which are the building blocks of quantum computers. However, usual QPT procedure…

2019-09-18abs ↗pdf ↗

Efficient SGPRN model for imputation and visualization of missing data.

problem Imputation and visualization of missing data in time-varying correlation.
method Stochastic collapsed variational inference with structured Gaussian process regression network.
result Our model provides better imputation results on missing data than state-of-the-art methods.