Coping with errors in binary search procedures

R. L. Rivest, A. R. Meyer, D. J. Kleitman, K. Winklmann, Joel Spencer

Research output: Contribution to journalConference article

Abstract

We consider the problem of identifying an unknown value xe{l, 2,⋯,n} using only comparisons of x to constants when as many as E of 'the comparisons may receive erroneous answers. For a continuous analogue of this problem we show that there is a unique strategy that is optimal in the worst case. This strategy for the continuous problem is then shown to yield a strategy for the original discrete problem that uses log2n+E-log2log2n+O(E-Iog2E) comparisons in the worst case. This number is shown to be optimal even if arbitrary "Yes-No" questions are allowed. We show that a modified version of this search problem with errors is equivalent to the problem of finding the minimal root of a set of increasing functions. The modified version is then also shown to be of complexity log2n+E-log2log2n+0(E-log2E).

Original languageEnglish (US)
Pages (from-to)227-232
Number of pages6
JournalProceedings of the Annual ACM Symposium on Theory of Computing
DOIs
StatePublished - May 1 1978
Event10th Annual ACM Symposium on Theory of Computing, STOC 1978 - San Diego, United States
Duration: May 1 1978May 3 1978

ASJC Scopus subject areas

  • Software

Cite this

Coping with errors in binary search procedures. / Rivest, R. L.; Meyer, A. R.; Kleitman, D. J.; Winklmann, K.; Spencer, Joel.

In: Proceedings of the Annual ACM Symposium on Theory of Computing, 01.05.1978, p. 227-232.

Research output: Contribution to journalConference article

Rivest, R. L. ; Meyer, A. R. ; Kleitman, D. J. ; Winklmann, K. ; Spencer, Joel. / Coping with errors in binary search procedures. In: Proceedings of the Annual ACM Symposium on Theory of Computing. 1978 ; pp. 227-232.
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