On-line Decision Making for a Class of Loss Functions via Lempel-Ziv Parsing

  • Authors:
  • Marcelo J. Weinberger;Erik Ordentlich

  • Affiliations:
  • -;-

  • Venue:
  • DCC '00 Proceedings of the Conference on Data Compression
  • Year:
  • 2000

Quantified Score

Hi-index 0.00

Visualization

Abstract

Prefetching in computer memory architectures is formalized as a sequential decision problem in which the instantaneous losses depend not only on the current action-observation pair, as in the traditional formulation, but also on past pairs. Motivated by the prefetching application, we study a class of loss functions that admit an efficient on-line decision algorithm. The algorithm uses the LZ78 parsing rule to dynamically build a tree, different from the classical LZ78 tree, and makes decisions based on the current node in a traversal path, determined by the sequence of observations. The asymptotic performance is essentially as good as that of the best finite-state strategy determined in hindsight, with full knowledge of the given sequence of observations. The related notion of delayed FS predictability is introduced, and its properties are studied.