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arXiv · 1206.3618

Sparse Sequential Dirichlet Coding

Joel Veness·Marcus Hutter
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Abstract

This short paper describes a simple coding technique, Sparse Sequential Dirichlet Coding, for multi-alphabet memoryless sources. It is appropriate in situations where only a small, unknown subset of the possible alphabet symbols can be expected to occur in any particular data sequence. We provide a competitive analysis which shows that the performance of Sparse Sequential Dirichlet Coding will be close to that of a Sequential Dirichlet Coder that knows in advance the exact subset of occurring alphabet symbols. Empirically we show that our technique can perform similarly to the more computationally demanding Sequential Sub-Alphabet Estimator, while using less computational resources.

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Joel Veness, Marcus Hutter. 2012-06-16. Sparse Sequential Dirichlet Coding. https://arxiv.org/abs/1206.3618

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