Work

A scalable trust-region algorithm with application to mixed-norm regression

Year: 2010
Type: conference-paper
Abstract: We present a new algorithm for minimizing a convex loss-function subject to regularization. Our framework applies to numerous problems in machine learning and statistics; notably, for sparsity-promoting regularizers such as l_1 or l_{1,infty} norms it enables efficient computation of sparse solutions. Our approach is based on the trust-region framework with nonsmooth objectives, which allows us to build on known results to provide convergence analysis. We avoid the computational overheads associated with the conventional Hessian approximation used by trust-region methods by instead using a simple separable quadratic approximation. This approximation also enables use of proximity operators for tackling nonsmooth regularizers. We illustrate the versatility of our resulting algorithm by specializing it to three mixed-norm regression problems: group lasso [36], group logistic regression [21], and multi-task lasso [19]. We experiment with both synthetic and real-world large-scale data—our method is seen to be com\npetitive, robust, and scalable.
Language: English
Open Access status: green
OpenAlex ID: W2141760723
FWCI: 13.54
Cites: 37
Cited by: 31
Related to: 10