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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.

168,695 papers · 148 categories

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214428641855 · Jun 202019922001200920172026
48 results for complex correlation structures

This study analyzes cryptocurrency market dynamics using a novel qq-dependent detrended cross-correlation method.

problem Capturing correlations at varying fluctuation amplitudes and time scales in complex systems.
method Extends traditional metrics with qq-dependent detrended cross-correlation coefficient ρ(q,s) and qqMSTs.
result Significant shifts in network structures during major disruptions, leading to decentralized correlations.

CADGMM detects anomalies by capturing complex correlations in data.

problem Detecting anomalies in complex, unstructured data.
method CADGMM uses a graph structure to encode correlations, then a dual-encoder to learn low-dimensional latent space, followed by a Gaussian Mixture Model for anomaly detection.
result CADGMM effectively detects anomalies in real-world datasets.

We analyze the daily stock data of the Nasdaq Composite index in the 22-year period 1992-2013 and identify market states as clusters of correlation matrices with similar correlation structures. We investigate the stability of the correlation structure of each state by estimating the statistical fluctuations of correlat…

2014-06-20abs ↗pdf ↗

Improved sample complexity for Gaussian Mixture Models using Pair Correlation Factor.

problem Understanding the sample complexity of Gaussian Mixture Models.
method Introducing Pair Correlation Factor (PCF) to measure clustering of component means and improving sample complexity bounds.
result The Pair Correlation Factor (PCF) more accurately determines the difficulty of parameter recovery in Gaussian Mixture Models.

This paper introduces anti-correlation networks to study China's stock market.

problem Previous studies ignored anti-correlation in financial networks.
method Constructed weighted temporal anti-correlation and positive correlation networks.
result Unveiled differences in topological measurements between anti-correlation and positive correlation networks.

The properties of q-dependent cross-correlation matrices of stock market have been analyzed by using the random matrix theory and complex network. The correlation structures of the fluctuations at different magnitudes have unique properties. The cross-correlations among small fluctuations are much stronger than those a…

2017-04-13abs ↗pdf ↗

Study analyzes landscape complexity of empirical loss functions with correlated data.

problem Understanding the complexity of loss landscapes in machine learning with structured data.
method Kac-Rice formula and random matrix theory applied to high-dimensional empirical loss functions.
result Characterizes the average number of critical points in loss functions with structured data.

Study analyzes stock market correlations using multivariate distributions.

problem Capturing the correlation structure of complex, non-stationary systems.
method Applied Random Matrix Model to empirical data of 479 US stocks.
result Described and quantified changes in empirical distributions due to non-stationarity.

Improved eigenvalue distribution method for financial data.

problem Noise and complexity in financial markets.
method Matrix H theory, hierarchical structure, informational cascade.
result Captures a larger fraction of data variance in financial markets.

In this paper, we present a hypergraph neural networks (HGNN) framework for data representation learning, which can encode high-order data correlation in a hypergraph structure. Confronting the challenges of learning representation for complex data in real practice, we propose to incorporate such data structure in a hy…

2018-09-25abs ↗pdf ↗

The paper analyzes Nordic stock markets' correlation structures and regime shifts.

problem Understanding and exploiting regime shifts in Nordic stock markets.
method Examined two decades of daily data for OMXS30, OMXC20, and OMXH25 universes; proposed an adaptive portfolio allocation framework.
result Documented pronounced regime dependence in rolling correlation matrices; proposed an adaptive portfolio allocation framework.

World currency network constitutes one of the most complex structures that is associated with the contemporary civilization. On a way towards quantifying its characteristics we study the cross correlations in changes of the daily foreign exchange rates within the basket of 60 currencies in the period December 1998 -- M…

2007-08-31abs ↗pdf ↗

Financial markets are highly correlated systems that reveal both the inter-market dependencies and the correlations among their different components. Standard analyzing techniques include correlation coefficients for pairs of signals and correlation matrices for rich multivariate data. In the latter case one constructs…

2006-05-15abs ↗pdf ↗

The paper explores local-correlation models for pricing complex financial contracts.

problem Calibrating synthetic quanto forward contracts and composite options.
method Design on-line calibration procedures for local and stochastic volatility models.
result Calibration performance of local-correlation models compared to simpler approximations.

Study uses topological signatures to quantify financial market complexity.

problem Capturing temporal organization beyond volatility measures.
method Null validated topological approach using L1L^1 norm of persistence landscapes.
result Persistence landscape norms reveal dynamical structure during market stress.

In this paper we provide evidence that financial option markets for equity indices give rise to non-trivial dependency structures between its constituents. Thus, if the individual constituent distributions of an equity index are inferred from the single-stock option markets and combined via a Gaussian copula, for examp…

2009-09-18abs ↗pdf ↗

Diffusion models learn simple statistics before complex ones, revealing a sample complexity exponent.

problem Understanding the learning dynamics of diffusion models.
method Empirical observations and theoretical analysis of diffusion models and denoisers.
result Diffusion models learn simple statistics (pair-wise correlations) at linear sample complexity, while higher-order statistics (e.g., fourth cumulant) require cubic sample complexity.

We analyze the spectral properties of correlation matrices between distinct statistical systems. Such matrices are intrinsically non symmetric, and lend themselves to extend the spectral analyses usually performed on standard Pearson correlation matrices to the realm of complex eigenvalues. We employ some recent random…

2012-01-31abs ↗pdf ↗

This paper looks into the analysis of the long-range auto-correlations and cross-correlations in bond market. Based on Detrended Moving Average (DMA) method, empirical results present a clear evidence of long-range persistence that exists in one year scale. The degree of long-range correlation related to maturities has…

2016-10-31abs ↗pdf ↗

We uncover scaling laws and statistical structure in complex datasets.

problem Understanding universal traits in complex datasets.
method Analogizing data to physical systems, using statistical physics and RMT.
result Real-world datasets and Gaussian data with long-range correlations share the same RMT universality class.

Study uses detrended cross-correlation to analyze cryptocurrency market, revealing robust collective modes and distinguishing interdependencies.

problem Nonstationarity, long-range memory, and heavy-tailed fluctuations obscure traditional correlations in complex systems.
method Constructs detrended correlation matrices using multifractal detrended cross-correlation coefficient ρrρ_r to emphasize different fluctuations.
result Detrending and fluctuation analysis reveal distinct spectral properties from random case, identifying market and sectoral components.

Paper analyzes sample complexity for offline RL with deep ReLU networks.

problem Theoretical analysis of sample complexity for offline RL with deep ReLU networks.
method Establishes sample complexity for offline RL with deep ReLU networks, considering Besov dynamic closure and correlated structure.
result First theoretical characterization of sample complexity for offline RL with deep neural network function approximation.

New AMP algorithms for rotationally invariant models with reduced complexity.

problem Signal estimation in generalized linear models with arbitrary spectral design matrices.
method Rotationally invariant approximate message passing (AMP) algorithms.
result Performance close to Vector AMP with significantly lower complexity.

We present a new method for articulating scale-dependent topological descriptions of the network structure inherent in many complex systems. The technique is based on "Partition Decoupled Null Models,'' a new class of null models that incorporate the interaction of clustered partitions into a random model and generaliz…

2008-05-22abs ↗pdf ↗

We study the dependency and causality structure of the cryptocurrency market investigating collective movements of both prices and social sentiment related to almost two thousand cryptocurrencies traded during the first six months of 2018. This is the first study of the whole cryptocurrency market structure. It introdu…

2019-03-03abs ↗pdf ↗

Two new methods for analyzing repeated measures data using embeddings into Reproducing Kernel Hilbert Spaces.

problem Analyzing complex data structures with multiple features over time.
method Two generalizations of canonical correlation analysis for repeated measures data using embeddings into Reproducing Kernel Hilbert Spaces.
result Consistency rates for transformation and correlation estimators, relaxing common assumptions.

The inference of correlated signal fields with unknown correlation structures is of high scientific and technological relevance, but poses significant conceptual and numerical challenges. To address these, we develop the correlated signal inference (CSI) algorithm within information field theory (IFT) and discuss its n…

2016-12-26abs ↗pdf ↗

Stock price movement reveals complex interdependencies that are simplified through linear correlation.

problem Exploring the spectral dynamics of the Indonesian capital market using structural network representations.
method Combining three dependency estimators (Pearson, MI adaptive binning, and MI-kNN) with two graph filtering schemes (MST and PMFG) and four community decoders.
result MI adaptive binning is shown to be more proportional than kNN for detecting residual information.

Research examines correlations of complex logarithms of lattice points, showing level repulsion and Poissonian behavior.

problem Analyzing correlations of complex logarithms of lattice points.
method Proving existence of pair correlation functions and examining behavior at various scalings.
result Level repulsion observed at linear scaling, Poissonian behavior at sublinear scalings.

Many recent developments in network analysis have focused on multilayer networks, which one can use to encode time-dependent interactions, multiple types of interactions, and other complications that arise in complex systems. Like their monolayer counterparts, multilayer networks in applications often have mesoscale fe…

2019-08-11abs ↗pdf ↗

Study topological correlators for SU(2)SU(2) SYM on four-manifolds, deriving explicit formulae and confirming S-duality.

problem Topological correlation functions of SU(2)SU(2), N=2\mathcal{N}=2^* SYM on four-manifolds.
method Coupling to a Spin^c structure, deriving explicit formulae, and confirming S-duality.
result Topological correlators are mock modular forms for b2+=1b_2^+=1.

Paper forecasts stock correlations using a hybrid model combining graph neural networks and transformers.

problem Improving stock correlation forecasts for better portfolio management.
method Hybrid model combining Transformer and graph attention networks for forecasting residual deviations from historical data.
result The hybrid model reduces correlation forecasting error compared to rolling-window estimates.

We started from computer experiments with simple one-dimensional ergodic dynamical systems called interval exchange transformations. Correlators in these systems decay as a power of time. In the simplest non-trivial case the exponent is equal to 1/3. We found a formula connecting characteristic exponents with explicit …

1997-01-28abs ↗pdf ↗