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arXiv · 2305.03850

A Non-Asymptotic Analysis of Mismatched Guesswork

Abstract

The problem of mismatched guesswork considers the additional cost incurred by using a guessing function which is optimal for a distribution $q$ when the random variable to be guessed is actually distributed according to a different distribution $p$. This problem has been well-studied from an asymptotic perspective, but there has been little work on quantifying the difference in guesswork between optimal and suboptimal strategies for a finite number of symbols. In this non-asymptotic regime, we consider a definition for mismatched guesswork which we show is equivalent to a variant of the Kendall tau permutation distance applied to optimal guessing functions for the mismatched distributions. We use this formulation to bound the cost of guesswork under mismatch given a bound on the total variation distance between the two distributions.

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BibTeXRIS

Alexander Mariona, Homa Esfahanizadeh, Rafael G. L. D'Oliveira, Muriel Médard. 2023-05-05. A Non-Asymptotic Analysis of Mismatched Guesswork. https://arxiv.org/abs/2305.03850

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