Title
Horizon-Independent Optimal Prediction with Log-Loss in Exponential Families
Abstract
We study online learning under logarithmic loss with regular parametric models. Hedayati and Bartlett (2012b) showed that a Bayesian prediction strategy with Jeffreys prior and sequential normalized maximum likelihood (SNML) coincide and are optimal if and only if the latter is exchangeable, and if and only if the optimal strategy can be calculated without knowing the time horizon in advance. They put forward the question what families have exchangeable SNML strategies. This paper fully answers this open problem for one-dimensional exponential families. The exchangeability can happen only for three classes of natural exponential family distributions, namely the Gaussian, Gamma, and the Tweedie exponential family of order 3/2. Keywords: SNML Exchangeability, Exponential Family, Online Learning, Logarithmic Loss, Bayesian Strategy, Jeffreys Prior, Fisher Information1
Year
Venue
DocType
2013
COLT
Journal
Volume
Citations 
PageRank 
abs/1305.4324
7
0.94
References 
Authors
8
5
Name
Order
Citations
PageRank
Peter L. Bartlett154821039.97
Peter Grunwald211311.40
Peter Harremoës318520.10
Fares Hedayati4102.58
Wojciech Kotlowski515816.32