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The information contained in multiple sibling pairs.

S E Hodge
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Abstract

In a sibship of size s, s(s-1)/2 sib pairs can be formed, but these pairs are statistically dependent when s greater than 2. This study examines how much independent information is obtained when all possible pairs are used to evaluate the sharing of genes identical by descent. A logarithmic measure of information, sigma pilog2pi [Shannon, 1948], is used. The basic unit of information is the binomial "bit," or the amount of information in the toss of a fair coin. It is shown that a single independent sib pair contains 1.5 bits. The complete sibship contains a total of 2s-3+(1/2)s-1 bits, or (2s-3+(1/2)s-1)/1.5 pair-equivalents of information. The information is reduced if all sib genotypes do not occur with equal probability.

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BiometryGenetic MarkersGenetics, MedicalGenotypeHumansModels, GeneticJournal ArticleResearch Support, U.S. Gov't, P.H.S.

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S E Hodge. 1984. The information contained in multiple sibling pairs.. https://doi.org/10.1002/gepi.1370010203

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