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Sufficiency in quantum statistical inference. A survey with examples

Anna Jencova·Denes Petz
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Abstract

This paper attempts to give an overview about sufficiency in the setting of quantum statistics. The basic concepts are treated paralelly to the the measure theoretic case. It turns out that several classical examples and results have a non-commutative analogue. Some of the results are presented without proof (but with exact references) and the presentation is intended to be self-contained. The main examples discussed in the paper are related the Weyl algebra and to the exponential family of states. The characterization of sufficiency in terms of quantum Fisher information is a new result.

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Anna Jencova, Denes Petz. 2006-04-12. Sufficiency in quantum statistical inference. A survey with examples. https://arxiv.org/abs/quant-ph/0604091

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