[Nouvelle P-valeur approchée d'alignements locaux de séquences avec gaps]
Nous proposons une nouvelle méthode pour estimer la signification statistique des alignements locaux de deux séquences avec gaps. On s'intéresse plus particulièrement aux séquences courtes pour lesquelles les méthodes standards sont moins efficaces étant donné leur aspect asymptotique. Notre approche combine une distribution approchée du score local sans gaps de deux séquences et une fonction de score spécifique qui permet d'introduire les gaps. Soit h un entier positif, la fonction de score est définie sur les h-uplets des composants des séquences et correspond au score global avec gap. L'influence de h et la qualité de la p-valeur sont ensuite étudiées numériquement.
We propose a new method to approximate the significativity of gapped local sequence alignments. We focus on short sequences for which standard methods are known to be less accurate since they have been developed under asymptotics. Our approach combines an approximate distribution of ungapped local score of two sequences and a special scoring scheme that allows the insertion of gaps. For a positive integer h, the scoring scheme is defined on h-tuples of the components of the sequences and corresponds to the gapped global score. The influence of h and the accuracy of the p-value are numerically studied.
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@article{CRMATH_2008__346_1-2_87_0,
author = {Fayyaz, Afshin M. and Mercier, Sabine and Ferr\'e, Louis and Hassenforder, Claudie},
title = {New approximate {\protect\emph{P}-value} of gapped local sequence alignments},
journal = {Comptes Rendus. Math\'ematique},
pages = {87--92},
publisher = {Elsevier},
volume = {346},
number = {1-2},
year = {2008},
doi = {10.1016/j.crma.2007.11.022},
language = {en},
url = {http://www.numdam.org/articles/10.1016/j.crma.2007.11.022/}
}
TY - JOUR AU - Fayyaz, Afshin M. AU - Mercier, Sabine AU - Ferré, Louis AU - Hassenforder, Claudie TI - New approximate P-value of gapped local sequence alignments JO - Comptes Rendus. Mathématique PY - 2008 SP - 87 EP - 92 VL - 346 IS - 1-2 PB - Elsevier UR - http://www.numdam.org/articles/10.1016/j.crma.2007.11.022/ DO - 10.1016/j.crma.2007.11.022 LA - en ID - CRMATH_2008__346_1-2_87_0 ER -
%0 Journal Article %A Fayyaz, Afshin M. %A Mercier, Sabine %A Ferré, Louis %A Hassenforder, Claudie %T New approximate P-value of gapped local sequence alignments %J Comptes Rendus. Mathématique %D 2008 %P 87-92 %V 346 %N 1-2 %I Elsevier %U http://www.numdam.org/articles/10.1016/j.crma.2007.11.022/ %R 10.1016/j.crma.2007.11.022 %G en %F CRMATH_2008__346_1-2_87_0
Fayyaz, Afshin M.; Mercier, Sabine; Ferré, Louis; Hassenforder, Claudie. New approximate P-value of gapped local sequence alignments. Comptes Rendus. Mathématique, Tome 346 (2008) no. 1-2, pp. 87-92. doi : 10.1016/j.crma.2007.11.022. http://www.numdam.org/articles/10.1016/j.crma.2007.11.022/
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