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20012026
most citedNoisy Covariance Matrices and Portfolio Optimization II

96 citations · 408 across the 7 of their papers we have counts for

collaborators

8 papers

cs.SE2026

Identical Runs, Different Results: Benchmarking AI Coding Agents on Open-Weight Models

Eduardo Ariño de la Rubia, Szilard Pafka

Repeated runs of the same coding agent are known to give different benchmark scores. We ask what that variation means for a team running an agent on its own task, by intensive repl…

physics.soc-ph2006★ 1 cited

Noise sensitivity of portfolio selection under various risk measures

Imre Kondor, Szilard Pafka, Gabor Nagy

We study the sensitivity to estimation error of portfolios optimized under various risk measures, including variance, absolute deviation, expected shortfall and maximal loss. We in…

physics.soc-ph2005★ 47 cited

Random Matrix Filtering in Portfolio Optimization

Gabor Papp, Szilard Pafka, Maciej A. Nowak +1

We study empirical covariance matrices in finance. Due to the limited amount of available input information, these objects incorporate a huge amount of noise, so their naive use in…

cond-mat.stat-mech2004★ 45 cited

Exponential Weighting and Random-Matrix-Theory-Based Filtering of Financial Covariance Matrices for Portfolio Optimization

Szilard Pafka, Marc Potters, Imre Kondor

We introduce a covariance matrix estimator that both takes into account the heteroskedasticity of financial returns (by using an exponentially weighted moving average) and reduces…

cond-mat.stat-mech2003★ 92 cited

Estimated Correlation Matrices and Portfolio Optimization

Szilard Pafka, Imre Kondor

Financial correlations play a central role in financial theory and also in many practical applications. From theoretical point of view, the key interest is in a proper description…

cond-mat.stat-mech2002★ 96 cited

Noisy Covariance Matrices and Portfolio Optimization II

Szilard Pafka, Imre Kondor

Recent studies inspired by results from random matrix theory [1,2,3] found that covariance matrices determined from empirical financial time series appear to contain such a high am…