Permutation P-values Should Never Be Zero: Calculating Exact P-values When Permutations Are Randomly Drawn
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چکیده
منابع مشابه
Permutation P-values should never be zero: calculating exact P-values when permutations are randomly drawn.
Permutation tests are amongst the most commonly used statistical tools in modern genomic research, a process by which p-values are attached to a test statistic by randomly permuting the sample or gene labels. Yet permutation p-values published in the genomic literature are often computed incorrectly, understated by about 1/m, where m is the number of permutations. The same is often true in the ...
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In this study, we show through the theory of order statistics that a considerable proportion of p-values will be under-evaluated by the permutation procedure. To solve this problem, we propose to conservatively adjust permutation p-values. The adjustment requires no parametric assumption on the distribution of test statistics. The solution can be expressed by a normalised incomplete beta functi...
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ژورنال
عنوان ژورنال: Statistical Applications in Genetics and Molecular Biology
سال: 2010
ISSN: 1544-6115
DOI: 10.2202/1544-6115.1585