# Cleaning large-dimensional covariance matrices for correlated samples.

@article{Burda2022CleaningLC, title={Cleaning large-dimensional covariance matrices for correlated samples.}, author={Zdzislaw Burda and Andrzej Jarosz}, journal={Physical review. E}, year={2022}, volume={105 3-1}, pages={ 034136 } }

We elucidate the problem of estimating large-dimensional covariance matrices in the presence of correlations between samples. To this end, we generalize the Marčenko-Pastur equation and the Ledoit-Péché shrinkage estimator using methods of random matrix theory and free probability. We develop an efficient algorithm that implements the corresponding analytic formulas based on the Ledoit-Wolf kernel estimation technique. We also provide an associated open-source Python library, called shrinkage…

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