Preprint
A Note on Choosing the Threshold for Large Covariance Estimations in Factor Models
ArXiv.org
Cornell University
08/30/2016
DOI: 10.48550/arxiv.1608.08318
Abstract
This note shows that for i.i.d. data, estimating large covariance matrices in factor models can be casted using a simple plug-in method to choose the threshold:
μjl = c0 √n Φ−1(1 – α 2p2 ) √ √ √ √ 1 n n∑ i=1̂ u2 jî u2 li.
This is motivated by the tuning parameter suggested by Belloni et al. (2012) in the lasso literature. It also leads to the minimax rate of convergence of the large covariance matrix estimator. Previously, the minimaxity is achievable only when n = o(p log p) by Fan et al. (2013), and now this condition is weakened to n = o(p2 log p). Here n denotes the sample size and p denotes the dimension.
Details
- Title: Subtitle
- A Note on Choosing the Threshold for Large Covariance Estimations in Factor Models
- Creators
- Yuan Liao
- Resource Type
- Preprint
- Publication Details
- ArXiv.org
- DOI
- 10.48550/arxiv.1608.08318
- ISSN
- 2331-8422
- Publisher
- Cornell University; Ithaca, New York
- Language
- English
- Date posted
- 08/30/2016
- Academic Unit
- Economics
- Record Identifier
- 9984937927202771
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