Title
A Quasi-Newton Approach to Nonsmooth Convex Optimization Problems in Machine Learning
Abstract
We extend the well-known BFGS quasi-Newton method and its memory-limited variant LBFGS to the optimization of nonsmooth convex objectives. This is done in a rigorous fashion by generalizing three components of BFGS to subdifferentials: the local quadratic model, the identification of a descent direction, and the Wolfe line search conditions. We prove that under some technical conditions, the resulting subBFGS algorithm is globally convergent in objective function value. We apply its memory-limited variant (subLBFGS) to L2-regularized risk minimization with the binary hinge loss. To extend our algorithm to the multiclass and multilabel settings, we develop a new, efficient, exact line search algorithm. We prove its worst-case time complexity bounds, and show that our line search can also be used to extend a recently developed bundle method to the multiclass and multilabel settings. We also apply the direction-finding component of our algorithm to L1-regularized risk minimization with logistic loss. In all these contexts our methods perform comparable to or better than specialized state-of-the-art solvers on a number of publicly available data sets. An open source implementation of our algorithms is freely available.
Year
DOI
Venue
2010
10.1145/1756006.1756045
Journal of Machine Learning Research
Keywords
Field
DocType
bundle method,multilabel setting,nonsmooth convex optimization problems,machine learning,available data set,l1-regularized risk minimization,subbfgs algorithm,logistic loss,quasi-newton approach,l2-regularized risk minimization,exact line search algorithm,wolfe line search condition,line search,quasi newton method,time complexity,convex optimization,objective function
Mathematical optimization,Hinge loss,Generalization,Descent direction,Line search,Minification,Artificial intelligence,Time complexity,Broyden–Fletcher–Goldfarb–Shanno algorithm,Convex optimization,Mathematics,Machine learning
Journal
Volume
ISSN
Citations 
11,
Journal of Machine Learning Research 11(Mar):1145-1200, 2010
32
PageRank 
References 
Authors
1.90
21
4
Name
Order
Citations
PageRank
Jin Yu1863.68
S. V. N. Vishwanathan21991131.90
Simon Günter358834.93
Nicol N. Schraudolph41185164.26