Title
Minimum and maximum against k lies
Abstract
A neat 1972 result of Pohl asserts that ⌈3n/2 ⌉−2 comparisons are sufficient, and also necessary in the worst case, for finding both the minimum and the maximum of an n-element totally ordered set. The set is accessed via an oracle for pairwise comparisons. More recently, the problem has been studied in the context of the Rényi–Ulam liar games, where the oracle may give up to k false answers. For large k, an upper bound due to Aigner shows that $(k+{\mathcal O}(\sqrt{k}))n$ comparisons suffice. We improve on this by providing an algorithm with at most $(k+1+C)n+{\mathcal O}(k^3)$ comparisons for some constant C. The known lower bounds are of the form (k+1+ck)n−D, for some constant D, where c0=0.5, $c_1=\frac{23}{32}= 0.71875$, and $c_k={\mathrm{\Omega}}(2^{-5k/4})$ as k→∞.
Year
DOI
Venue
2010
10.1007/978-3-642-13731-0_14
Clinical Orthopaedics and Related Research
Keywords
DocType
Volume
ulam liar game,large k,constant c.,k false answer,comparisons suffice,worst case,mathcal o,pairwise comparison,lower bound,constant d,total order,upper bound
Conference
2012
ISSN
ISBN
Citations 
0302-9743
3-642-13730-X
0
PageRank 
References 
Authors
0.34
7
4
Name
Order
Citations
PageRank
Michael Hoffmann122722.74
Jiří Matoušek21711179.65
Yoshio Okamoto317028.50
Philipp Zumstein4143.45