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

4138251,2381,650 · Jun 202019922001200920172026
48 results for known observation model

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.

Improved POMDP regret to sqrt(T) with known observation model.

problem Average-reward POMDPs with unknown transition model but known observation model.
method Optimistic algorithm using deterministic policies and novel estimation techniques.
result First approach with regret guarantee of sqrt(T) against optimal policy.

Estimates linear models from self-selected data, addressing econometric challenges.

problem Estimating linear models from self-selected data with known or unknown selection criteria.
method Developed efficient algorithms for both known and unknown selection criteria.
result Identified and estimated linear models from self-selected data, accommodating various selection criteria.

Two algorithms for nonlinear systems with unknown inputs are compared and implemented.

problem Analysis and comparison of algorithms for nonlinear systems with unknown inputs.
method Two symbolic algorithms, ORC-DF and FISPO, are compared and implemented in a MATLAB toolbox.
result FISPO is more generally applicable, while ORC-DF is more efficient for affine input models.

Identifies causal effects in partially directed acyclic graphs with observed variables.

problem Identifying conditional causal effects in graphs with background knowledge and observed variables.
method Three results: identification formula, do calculus generalization, and algorithm completeness.
result Complete algorithm for identifying conditional effects in MPDAGs.

New algorithm learns POMDPs with known observation model efficiently.

problem Learning POMDPs with unknown transition model in average-reward setting.
method OAS estimation technique and OAS-UCRL algorithm balancing exploration-exploitation.
result Regret guarantee of order O(Tlog(T))\mathcal{O}(\sqrt{T \log(T)}) for OAS-UCRL algorithm.

This paper advances sample-efficient learning for partially observable RL by introducing B-stability and new algorithms.

problem Hard sample complexity for learning near-optimal policies in partially observable RL.
method Proposes B-stability as a unified structural condition and develops new algorithms for sample-efficient learning.
result Any B-stable PSR can be learned with polynomial samples, improving over current best complexities.

Paper models graph edge dependencies using latent variables for community detection.

problem Graphs' edge dependencies not fully explained by community membership.
method Introduces auxiliary latent variables to model edge dependencies and analyzes conditions for exact recovery.
result Exact recovery possible by semidefinite programming down to maximum likelihood threshold.

Cluster analysis methods seek to partition a data set into homogeneous subgroups. It is useful in a wide variety of applications, including document processing and modern genetics. Conventional clustering methods are unsupervised, meaning that there is no outcome variable nor is anything known about the relationship be…

2013-07-01abs ↗pdf ↗

This work studies the problem of batch off-policy evaluation for Reinforcement Learning in partially observable environments. Off-policy evaluation under partial observability is inherently prone to bias, with risk of arbitrarily large errors. We define the problem of off-policy evaluation for Partially Observable Mark…

2019-09-09abs ↗pdf ↗

We study the computational tractability of PAC reinforcement learning with rich observations. We present new provably sample-efficient algorithms for environments with deterministic hidden state dynamics and stochastic rich observations. These methods operate in an oracle model of computation -- accessing policy and va…

2018-03-01abs ↗pdf ↗

The paper introduces a new method to characterize cosmological models using observer-based invariants.

problem Equivalence problem for cosmological models in four-dimensional gravity theories.
method Modified Cartan-Karlhede algorithm adapted to fundamental observers, including derivatives of the time-like vector field.
result A list of invariants that completely characterize cosmological models, independent of coordinates.

This paper uses a generalization of symplectic geometry, known as nn-symplectic geometry and developed by Norris, to find observables on three-dimensional manifolds. It will be seen that for the cases considered, the nn-symplectic observables are derivable from the symplectic observables of C2C^2. The quantization of…

1997-10-24abs ↗pdf ↗

ParKCa combines multiple causal inference methods to infer new causes from known and unknown factors.

problem Causal inference from observational data when randomized experiments are not feasible.
method ParKCa uses a stacking approach to combine results from multiple causal inference methods.
result ParKCa infers more causes than existing methods in real-world and simulated datasets.

The framework of variational autoencoders allows us to efficiently learn deep latent-variable models, such that the model's marginal distribution over observed variables fits the data. Often, we're interested in going a step further, and want to approximate the true joint distribution over observed and latent variables…

2019-07-10abs ↗pdf ↗

Efficiently learns Gaussian distributions from censored data with known missingness patterns.

problem Learning high-dimensional Gaussian distributions from data with missing values.
method Developed algorithms for self-censoring and linear thresholding scenarios.
result Achieved efficient learning of Gaussian distributions up to a specified total variation distance.

Stress shocks are often calculated as multiples of the standard deviation of a history set. This paper investigates how many standard deviations are required to guarantee that this shock exceeds any observation within the history set, given the additional constraint of kurtosis. The results of this analysis are then us…

2019-05-24abs ↗pdf ↗

Paper explores supervised learning methods to approximate ideal observer for joint signal detection and localization.

problem Optimizing medical imaging systems by assessing their performance using the Ideal Observer model.
method Uses supervised learning methods, specifically convolutional neural networks, to approximate the Ideal Observer for joint signal detection and localization tasks.
result Supervised learning-based methods can approximate the Ideal Observer for joint signal detection and localization tasks, as shown by comparisons to MCMC and analytical methods.

We present a simple model of a stock market where a random communication structure between agents gives rise to a heavy tails in the distribution of stock price variations in the form of an exponentially truncated power-law, similar to distributions observed in recent empirical studies of high frequency market data. Ou…

1997-12-30abs ↗pdf ↗

Estimates classification rules from partially classified data.

problem Estimating Bayes' rule for unclassified observations in partially classified data.
method Fitting a g-component mixture model by maximum likelihood (ML) via the EM algorithm.
result Asymptotic relative efficiency (ARE) of Bayes' rule estimated from partially classified samples.

This paper examines a heterogeneous beliefs model in which there is a process that is only partially observed by the agents. The economy contains a risky asset producing dividends continuously in time. The dividends are observed by the agents. The dividends are assumed to be a known function of some other unobserved pr…

2009-07-28abs ↗pdf ↗

Finite mixture models are statistical models which appear in many problems in statistics and machine learning. In such models it is assumed that data are drawn from random probability measures, called mixture components, which are themselves drawn from a probability measure P over probability measures. When estimating …

2015-02-23abs ↗pdf ↗

Autoregressive state transitions, where predictions are conditioned on past predictions, are the predominant choice for both deterministic and stochastic sequential models. However, autoregressive feedback exposes the evolution of the hidden state trajectory to potential biases from well-known train-test discrepancies.…

2019-08-30abs ↗pdf ↗

New Thompson Sampling for partially observed context bandits reduces regret logarithmically with time.

problem Improving Thompson Sampling for partially observed context bandits.
method Proposed a Thompson Sampling algorithm for partially observable contextual multi-armed bandits with theoretical performance guarantees.
result Regret scales logarithmically with time and the number of arms, and linearly with the dimension.

Despite the major advances taken in causal modeling, causality is still an unfamiliar topic for many statisticians. In this paper, it is demonstrated from the beginning to the end how causal effects can be estimated from observational data assuming that the causal structure is known. To make the problem more challengin…

2014-03-05abs ↗pdf ↗

Paper achieves logarithmic regret for online Kalman filter learning.

problem Predicting observations from an unknown, partially observed linear system with stochastic noise.
method Online least-squares algorithm exploiting the approximate linearity of Kalman filter predictions.
result Achieves regret of order poly(log(N)) with high probability.

We consider arbitrage free valuation of European options in Black-Scholes and Merton markets, where the general structure of the market is known, however the specific parameters are not known. In order to reflect this subjective uncertainty of a market participant, we follow a Bayesian approach to option pricing. Here …

2016-02-15abs ↗pdf ↗

SurvFM-RMST converts survival outcomes into pseudo-observation targets for tabular models.

problem Right-censored follow-up prevents direct use of survival labels in tabular patient data.
method SurvFM-RMST framework that converts survival outcomes into jackknife pseudo-observation targets for restricted mean survival time.
result SurvFM-RMST accurately recovered restricted event-free time in simulations and outperformed naive targets in static datasets.

A new approach to learning in brain-like networks using adversarial algorithms.

problem Complex inter-dependencies in brain-like networks not compatible with conditional independence assumptions.
method Adversarial algorithm for learning models of perceptual processing.
result The approach can mimic known neural phenomena and yields testable hypotheses.

We consider the problem of reconstructing a signal from under-determined modulo observations (or measurements). This observation model is inspired by a (relatively) less well-known imaging mechanism called modulo imaging, which can be used to extend the dynamic range of imaging systems; variations of this model have al…

2018-12-03abs ↗pdf ↗

Study evaluates machine learning for predicting treatment effects in observational studies.

problem Challenges in measuring treatment effects due to confounding bias in observational studies.
method Simulated two scenarios with and without confounding, using linear and non-linear relationships. Used machine learning models (linear regression, lasso regression, random forest) to predict counterfactuals and treatment effects.
result Machine learning models perform well under linearity but poorly under non-linearity, even in the presence of confounding.

We consider the problem of Robust PCA in the fully and partially observed settings. Without corruptions, this is the well-known matrix completion problem. From a statistical standpoint this problem has been recently well-studied, and conditions on when recovery is possible (how many observations do we need, how many co…

2016-05-25abs ↗pdf ↗

In this article we raise some new questions about positive definite functions on free groups, and explain how these are related to more well-known questions. The article is intended as a survey of known results that also offers some new perspectives and interesting observations; therefore the style is expository.

2019-06-04abs ↗pdf ↗

Neural Laplace Control tackles offline RL for continuous-time delayed systems with irregular observations.

problem Offline reinforcement learning problems involving continuous-time environments with delays and irregular observations.
method Combines a Neural Laplace dynamics model with a model predictive control (MPC) planner.
result Achieves near expert policy performance on continuous-time delayed environments.

Reinforcement learning would enjoy better success on real-world problems if domain knowledge could be imparted to the algorithm by the modelers. Most problems have both hidden state and unknown dynamics. Partially observable Markov decision processes (POMDPs) allow for the modeling of both. Unfortunately, they do not p…

2012-12-12abs ↗pdf ↗