COLLOQUIUM
3:00 p.m., Wednesday (January 30, 2008)
WMAX 110 (PIMS)
Sebastien Roch
Microsoft Research
Reconstructing the Tree of Life: Building Large Trees from Short Sequences
Abstract: Markov models on trees (MMT) arise naturally in many areas of science, notably
in Molecular Biologyas models of evolutionand in Statistical Physics
as models of spin systems. In this talk, I will discuss various MMT inference
problems motivated by applications in Statistical Phylogenetics, i.e., the
reconstruction of evolutionary histories of organisms from their molecular
sequences. I will begin with the "ancestral reconstruction" problem: how
accurately can one guess the sequence of a deep ancestor, given the sequences
of its current descendants? I will also discuss the related "phylogenetic
reconstruction" problem: given the sequences of a set of species, how efficiently
can one reconstruct their evolutionary history? Through deep connections between
these two problems and insights from Statistical Physics, I will show that one
can design novel, provably optimal reconstruction techniques.
Refreshments will be served at 2:45 p.m. (PIMS Lounge).
