Jump to Content

No-Regret Algorithms for Unconstrained Online Convex Optimization

Advances in Neural Information Processing Systems (NIPS) (2012)


Some of the most compelling applications of online convex optimization, including online prediction and classification, are unconstrained: the natural feasible set is R^n. Existing algorithms fail to achieve sub-linear regret in this setting unless constraints on the comparator point x* are known in advance. We present algorithms that, without such prior knowledge, offer near-optimal regret bounds with respect to any choice of x*. In particular, regret with respect to x* = 0 is constant. We then prove lower bounds showing that our guarantees are near-optimal in this setting.

Research Areas