Some Algorithms and Paradigms for Big Data

[摘要] The reality of big data poses both opportunities and challenges to modern researchers. Its key features -- large sample sizes, high-dimensional feature spaces, and structural complexity -- enforce new paradigms upon the creation of effective yet algorithmic efficient data analysis algorithms. In this dissertation, we illustrate a few paradigms through the analysis of three new algorithms. The first two algorithms consider the problem of phase retrieval, in which we seek to recover a signal from random rank-one quadratic measurements. We first show that an adaptation of the randomized Kaczmarz method provably exhibits linear convergence so long as our sample size is linear in the signal dimension. Next, we show that the standard SDP relaxation of sparse PCA yields an algorithm that does signal recovery for sparse, model-misspecified phase retrieval with a sample complexity that scales according to the square of the sparsity parameter. Finally, our third algorithm addresses the problem of Non-Gaussian Component Analysis, in which we are trying to identify the non-Gaussian marginals of a high-dimensional distribution. We prove that our algorithm exhibits polynomial time convergence with polynomial sample complexity.

[发布机构] University of Michigan

[效力级别] optimization

[关键词] big data;optimization;mathematical data science;machine learning;signal processing;Mathematics;Science;Mathematics