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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

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316192122 · Feb 202019922001200920172026
48 results for Oxygen Extraction Fraction

This work improves the accuracy of OEF and DBV maps from qBOLD MRI data.

problem Noisy and inaccurate inference of OEF and DBV from qBOLD MRI data.
method Flexible amortized variational inference using a scaled multivariate logit-Normal distribution.
result Smooth and physiologically plausible OEF and DBV maps inferred with fewer training data.

The study analyzes river water quality using statistical and machine learning methods.

problem Analyzing spatio-temporal dynamics of dissolved oxygen in the River Thames.
method Superstatistical methods and machine learning (e.g., Light Gradient Boosting Machine, Informer model).
result The Informer model outperforms others in long-term dissolved oxygen concentration forecasting.

MTL improves multi-dimensional regression in luminescence sensing.

problem Challenges in modeling multi-dimensional regression problems with classical methods.
method Multi-task learning (MTL) with feed-forward neural networks (FFNNs).
result MTL allows predicting multiple parameters from a single set of measurements.

Novel spatio-temporal LSTM model forecasts oceanic variables across sensors and scales.

problem Data sparsity and lack of connected spatial and temporal information in environmental datasets.
method SPATIAL LSTM architecture that learns across spatial and temporal scales.
result Framework accurately forecasts oceanic variables with comparable performance to state-of-the-art models.

Study finds racial bias in pulse oximeter readings has minimal impact on ICU ventilation rates.

problem Racial disparities in pulse oximeter readings affect clinical decisions in ICU settings.
method Causal inference using path-specific effects and doubly robust estimator.
result Minimal impact of racial discrepancies on invasive ventilation rates, but more pronounced on ventilation duration.

Tree-based model averaging improves CATE estimation from diverse sites.

problem Limited sample size and privacy concerns prevent accurate personalized treatment effect estimation.
method Tree-based model averaging approach to estimate CATEs from multiple heterogeneous sites.
result Improved accuracy in estimating conditional average treatment effects (CATEs) across sites.

We propose a simple auto-encoder framework for molecule generation. The molecular graph is first encoded into a continuous latent representation zz, which is then decoded back to a molecule. The encoding process is easy, but the decoding process remains challenging. In this work, we introduce a simple two-step decodin…

2019-06-08abs ↗pdf ↗

fSDE-Net generates time series with long-term memory using neural networks.

problem Generating time series with long-term memory from irregularly sampled data.
method fSDE-Net: neural fractional Stochastic Differential Equation Network using fractional Brownian motion.
result fSDE-Net can replicate distributional properties of real time-series data.

Recently, machine learning algorithms have successfully entered large-scale real-world industrial applications (e.g. search engines and email spam filters). Here, the CPU cost during test time must be budgeted and accounted for. In this paper, we address the challenge of balancing the test-time cost and the classifier …

2012-10-09abs ↗pdf ↗

New method combines long-memory reservoirs for accurate dengue forecasting from short data.

problem Accurate dengue forecasting from short, noisy, non-stationary, and nonlinear data.
method Fractional ESN and Wavelet ESN frameworks integrating long-term memory.
result fESN and wESN outperform baselines in multiple dengue datasets and forecasting horizons.

Thanks to the rise of wearable and connected devices, sensor-generated time series comprise a large and growing fraction of the world's data. Unfortunately, extracting value from this data can be challenging, since sensors report low-level signals (e.g., acceleration), not the high-level events that are typically of in…

2016-09-29abs ↗pdf ↗

There are a number of situations in which several signals are simultaneously recorded in complex systems, which exhibit long-term power-law cross-correlations. The multifractal detrended cross-correlation analysis (MF-DCCA) approaches can be used to quantify such cross-correlations, such as the MF-DCCA based on detrend…

2011-03-14abs ↗pdf ↗

Develops a risk score to assist ECMO planning for critically ill patients with viral or unspecified pneumonia.

problem Lack of a risk score to guide ECMO planning for critically ill patients.
method Leverages machine learning to develop the PEER score.
result PEER score predicts mortality and decompensation in patients eligible for ECMO.

Advances of modern sensing and sequencing technologies generate a deluge of high dimensional space-temporal physiological and next-generation sequencing (NGS) data. Physiological traits are observed either as continuous random functions, or on a dense grid and referred to as function-valued traits. Both physiological a…

2014-10-27abs ↗pdf ↗

SidAE combines autoencoders and Siamese networks for self-supervised feature extraction.

problem Efficiently extract meaningful features from unlabeled data.
method Proposes SidAE, a combination of autoencoders and Siamese networks for self-supervised image classification.
result SidAE outperforms self-supervised baselines across multiple datasets and scenarios, especially with limited labeled data.

A common problem in a high energy physics experiment is extracting a signal from a much larger background. Posed as a classification task, there is said to be an imbalance in the number of samples belonging to the signal class versus the number of samples from the background class. In this work we provide a brief overv…

2019-05-01abs ↗pdf ↗

We introduce jet topics: a framework to identify underlying classes of jets from collider data. Because of a close mathematical relationship between distributions of observables in jets and emergent themes in sets of documents, we can apply recent techniques in "topic modeling" to extract jet topics from data with mini…

2018-01-31abs ↗pdf ↗

In this work we present a new approach on studying dynamical systems. Combining the two ways of expressing the uncertainty, using probabilistic theory and credibility theory, we have research the generalized fractional hybrid equations. We have introduced the concepts of generalized fractional Wiener process, generaliz…

2009-09-15abs ↗pdf ↗

Study assesses data-driven and physics-based SGS models for transcritical combustion.

problem Challenges in simulating high-pressure combustion systems due to complex fluid behaviors.
method Comparison of physics-based and random forest machine learning models in turbulent transcritical non-premixed flames.
result Random forest models can effectively model subgrid stresses, providing insight into their formation.

Introduces fractional k-dimensional measure bridging fractional length and area.

problem Defining fractional measures for dimensions between 0 and n-1.
method Introduces a parameterized fractional measure σσ that converges to Hausdorff measure.
result Fractional measure converges to Hausdorff measure with a known constant factor.

The theory of derivative of noninteger order goes back to Leibniz, Liouville and Riemann. Derivatives of fractional order have found many applications in recent studies in mechanics, physics, economics. In this paper we define the fractional tangent bundle on a manifold, using a method of Radu Miron. The fractional Lei…

2007-09-15abs ↗pdf ↗

Let SgS_g be a closed orientable surface of genus g2g \geq 2 and CC a simple closed nonseparating curve in FF. Let tCt_C denote a left handed Dehn twist about CC. A \textit{fractional power} of tCt_C of \textit{exponent} $\fraction{\ell}{n}$ is an $h \in \Mod(S_g)$ such that hn=tCh^n = t_C^{\ell}. Unlike a root of a $t…

2012-07-16abs ↗pdf ↗

We formulate the fractional Ricci flow theory for (pseudo) Riemannian geometries enabled with nonholonomic distributions defining fractional integro-differential structures, for non-integer dimensions. There are constructed fractional analogs of Perelman's functionals and derived the corresponding fractional evolution …

2010-04-05abs ↗pdf ↗

Functional connectivity refers to the temporal statistical relationship between spatially distinct brain regions and is usually inferred from the time series coherence/correlation in brain activity between regions of interest. In human functional brain networks, the network structure is often inferred from functional m…

2014-12-20abs ↗pdf ↗

The Garside group, as a generalization of braid groups and Artin groups of finite types, is defined as the group of fractions of a Garside monoid. We show that the semidirect product of Garside monoids is a Garside monoid. We use the semidirect product ZGn\mathbb Z\ltimes G^n of the infinite cyclic group Z\mathbb Z and…

2004-11-22abs ↗pdf ↗

Modeling financial markets with memory using fractional calculus and Brownian motion.

problem Capturing memory effects in financial markets using stochastic models.
method Fractional Langevin equation with colored noise generated by fractional Brownian motion.
result Anomalous marginal glass phase observed in some regions of the system.

In this paper we established the condition for a curve to satisfy stochas- tic fractional HP (Hamilton-Pontryagin) equations. These equations are described using It^o integral. We have also considered the case of stochastic fractional Hamiltonian equa- tions, for a hyperregular Lagrange function. From the stochastic fr…

2009-06-24abs ↗pdf ↗

Extends fractional LpL^p uncertainty principles with extremizers and stability results.

problem Investigating uncertainty principles in fractional LpL^p settings.
method Analyzing the fractional Schrödinger equation to find extremal functions and sharp constants.
result Proves stability of extremizers for fractional uncertainty inequalities.

Approximates derivative pricing under fractional stochastic volatility.

problem Derivative pricing under fractional stochastic volatility model.
method Approximate expression derived from deterministic functions and fractional Ornstein-Uhlenbeck process.
result Numerical simulations show the feasibility and effect of long-range dependencies on derivative prices.