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Spectral density of sparse sample covariance matrices. (English) Zbl 1120.15019

Summary: Applying the replica method of statistical mechanics, we evaluate the eigenvalue density of the large random matrix (sample covariance matrix) of the form \(J = A^{\mathrm T}A\), where \(A\) is an \(M \times N\) real sparse random matrix. The difference from a dense random matrix is the most significant in the tail region of the spectrum. We compare the results of several approximation schemes, focusing on the behaviour in the tail region.

MSC:

15B52 Random matrices (algebraic aspects)
15A18 Eigenvalues, singular values, and eigenvectors