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arXiv · 0903.0649

The Nonparanormal: Semiparametric Estimation of High Dimensional Undirected Graphs

Han Liu·John Lafferty·Larry Wasserman
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Abstract

Recent methods for estimating sparse undirected graphs for real-valued data in high dimensional problems rely heavily on the assumption of normality. We show how to use a semiparametric Gaussian copula--or "nonparanormal"--for high dimensional inference. Just as additive models extend linear models by replacing linear functions with a set of one-dimensional smooth functions, the nonparanormal extends the normal by transforming the variables by smooth functions. We derive a method for estimating the nonparanormal, study the method's theoretical properties, and show that it works well in many examples.

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Han Liu, John Lafferty, Larry Wasserman. 2009-03-03. The Nonparanormal: Semiparametric Estimation of High Dimensional Undirected Graphs. https://arxiv.org/abs/0903.0649

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