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arXiv · 1008.3310

Partially ordered secretaries

Ragnar Freij·Johan Wästlund
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Abstract

The elements of a finite nonempty partially ordered set are exposed at independent uniform times in $[0,1]$ to a selector who, at any given time, can see the structure of the induced partial order on the exposed elements. The selector's task is to choose online a maximal element. This generalizes the classical linear order secretary problem, for which it is known that the selector can succeed with probability $1/e$ and that this is best possible. We describe a strategy for the general problem that achieves success probability $1/e$ for an arbitrary partial order.

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Ragnar Freij, Johan Wästlund. 2010-10-06. Partially ordered secretaries. https://arxiv.org/abs/1008.3310

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