Statistical significance in biological sequence analysis

Statistical significance in biological sequence analysis

One of the major goals of computational sequence analysis is to find sequence similarities, which could serve as evidence of structural and functional conservation, as well as of evolutionary relations among the sequences. Since the degree of similarity is usually assessed by the sequence alignment score, it is necessary to know if a score is high enough to indicate a biologically interesting a...

Statistical Significance in Biological Sequence Comparison1

The statistical significance of biological data.

The pathological and clinical (may I even say surgical ?) approach has thus furnished us with a working hypothesis on which the function of the thymus gland may eventually be elucidated. There are still many difficulties in the way of a final solution, and progress is likely to be slow. It may be thought safer to return for the present to Galen's belief that the thymus is just a cushion to prot...

Estimating statistical significance of sequence alignments.

Algorithms that compare two proteins or DNA sequences and produce an alignment of the best matching segments are widely used in molecular biology. These algorithms produce scores that when comparing random sequences of length n grow proportional to n or to log(n) depending on the algorithm parameters. The Azuma-Hoeffding inequality gives an upper bound on the probability of large deviations of ...

Statistical significance of ungapped sequence alignments.

Statistical significance of a local sequence alignment depends not only on the similarity score and on the sequence lengths, but also on a length of the alignment. Dependence of the alignment significance on the length of the sequences has been analyzed earlier, and is based on the idea that the longer sequences have more chances to share a local similarity with a bigger score. To the best of o...