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Physical Sciences and Mathematics Commons

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Mathematics

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Research Scholars in Residence

1989

Articles 1 - 2 of 2

Full-Text Articles in Physical Sciences and Mathematics

Prophet Inequalities For Parallel Processes, Theodore P. Hill, D. P. Kennedy Nov 1989

Prophet Inequalities For Parallel Processes, Theodore P. Hill, D. P. Kennedy

Research Scholars in Residence

Generalizations of prophet inequalities for single sequences are obtained for optimal stopping of several parallel sequences of independent random variables. For example, if {Xi, j, 1 ≤ i ≤ n, 1 ≤ j < ∞} are independent non-negative random variables, then E(sup Xi,j) ≤ (n + 1) max sup {E(Xi,t): t is a stop rule for Xi,1, Xi,2, ...} and this bound is best possible. Applications are made to comparisons of the optimal expected returns of various alternative methods of stopping of parallel processes.


Optimal-Partitioning Inequalities In Classification And Multi-Hypotheses Testing, Theodore P. Hill, Y. L. Tong Sep 1989

Optimal-Partitioning Inequalities In Classification And Multi-Hypotheses Testing, Theodore P. Hill, Y. L. Tong

Research Scholars in Residence

Optimal-partitioning and minimax risk inequalities are obtained for the classification and multi-hypotheses testing problems. Best possible bounds are derived for the minimax risk for location parameter families, based on the tail concentrations and Levy concentrations of the distributions. Special attention is given to continuous distributions with the maximum likelihood ratio property and to symmetric unimodal continuous distributions. Bounds for general (including discontinuous) distributions are also obtained.