2013

Exact and Stable Covariance Estimation from Quadratic Sampling via Convex Programming

Chen, Yuxin, Chi, Yuejie, Goldsmith, Andrea

Understand

Statistical inference and information processing of high-dimensional data often require efficient and accurate estimation of their second-order statistics.

  • With rapidly changing data, limited processing power and storage at the acquisition devices, it is desirable to extract the covariance structure from a single pass over the data and a small number of stored measurements.
  • In this paper, we explore a quadratic (or rank-one) measurement model which imposes minimal memory requirements and low computational complexity during the sampling process, and is shown to be optimal in preserving various low-dimensional covariance structures.
  • Specifically, four popular structural assumptions of covariance matrices, namely low rank, Toeplitz low rank, sparsity, jointly rank-one and sparse structure, are investigated, while recovery is achieved via convex relaxation paradigms for the respective structure.

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