English

On the Finite-Sample Analysis of $\Theta$-estimators

Statistics Theory 2016-10-11 v3 Statistics Theory

Abstract

In large-scale modern data analysis, first-order optimization methods are usually favored to obtain sparse estimators in high dimensions. This paper performs theoretical analysis of a class of iterative thresholding based estimators defined in this way. Oracle inequalities are built to show the nearly minimax rate optimality of such estimators under a new type of regularity conditions. Moreover, the sequence of iterates is found to be able to approach the statistical truth within the best statistical accuracy geometrically fast. Our results also reveal different benefits brought by convex and nonconvex types of shrinkage.

Keywords

Cite

@article{arxiv.1512.03987,
  title  = {On the Finite-Sample Analysis of $\Theta$-estimators},
  author = {Yiyuan She},
  journal= {arXiv preprint arXiv:1512.03987},
  year   = {2016}
}