Abstract:

In this talk we will begin with an overview of: sequence matching and rare word analysis in biological sequences. It is of biological interest, in the case of sequence matching to assess statistically how significant the match is; whereas in word pattern analysis, to decide statistically whether a word is over-represented or under-represented. We will describe a powerful tool of approximation, namely the Chen-Stein method in Poisson and compound Poisson approximation and illustrate how this method is applied in this context.