Abstract
We obtain a weak law of large numbers for quadratic forms of a stationary regular time series, imposing no rate of convergence to zero of its covariance function. We show how this law can be applied in proving universality properties of limiting spectral distributions of sample covariance matrices. In particular, we give another derivation of a recent result of Merlevède and Peligrad, who studied sample covariance matrices generated by IID samples of long memory time series.
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The author thanks an anonymous reviewer for constructive comments that improved the paper.
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This work is supported by the Russian Science Foundation under Grant 14-21-00162.
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Yaskov, P. LLN for Quadratic Forms of Long Memory Time Series and Its Applications in Random Matrix Theory. J Theor Probab 31, 2032–2055 (2018). https://doi.org/10.1007/s10959-017-0767-z
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DOI: https://doi.org/10.1007/s10959-017-0767-z