The Annals of Statistics

The solution path of the generalized lasso

Ryan J. Tibshirani and Jonathan Taylor

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We present a path algorithm for the generalized lasso problem. This problem penalizes the 1 norm of a matrix D times the coefficient vector, and has a wide range of applications, dictated by the choice of D. Our algorithm is based on solving the dual of the generalized lasso, which greatly facilitates computation of the path. For D = I (the usual lasso), we draw a connection between our approach and the well-known LARS algorithm. For an arbitrary D, we derive an unbiased estimate of the degrees of freedom of the generalized lasso fit. This estimate turns out to be quite intuitive in many applications.

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Ann. Statist., Volume 39, Number 3 (2011), 1335-1371.

First available in Project Euclid: 4 May 2011

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Primary: 62-XX: STATISTICS

Lasso path algorithm Lagrange dual LARS degrees of freedom


Tibshirani, Ryan J.; Taylor, Jonathan. The solution path of the generalized lasso. Ann. Statist. 39 (2011), no. 3, 1335--1371. doi:10.1214/11-AOS878.

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Supplemental materials

  • Supplementary material: Proofs and technical details. A supplementary document that contains a number of proofs and technical details concerning “The solution path of the generalized lasso”.