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SBC Seminar 3rd Dec SciLifeLab Sthlm - Late announcement!

posted Nov 30, 2012, 1:39 AM by Johan Nylander
Just got this (very late) announcement of a highly interesting seminar next week(!), Monday 3rd Dec., 10:30, Lunch room, Floor 2, SciLifeLab Stockholm.

[Message from Francesco Vezzi 2012-Nov-30]

"Dear all,
next week there will be two SBC seminars:

Monday (Decembers the 3rd)  Megan Owen  will present us her recent work in a seminar titled "Statistics in the Space of Phylogenetic Trees".  
Megan Owen is a researcher at David R. Cheriton School of Computer Science at the University of Waterloo in Canada. Megan's current research focuses on using geometric spaces to represent, study, and analyze phylogenetic trees and networks, as well as tree-shaped data arising from medical imaging. She is also interested in mathematical and statistical problems related to understanding these spaces.

Tuesday (December the 4th) Emil Kölbeck will present us her her master thesis work (supervisor Erik Sonnhammer) in a seminar titled "Protein domain versatility scoring methods".

Both seminars will take place at 10.30  in the Lunch Room floor 2 at SciLifeLab Stockholm.

Megan Owen's Abstract:
We introduce new notions of mean and variance for a set or distribution of phylogenetic trees.  These definitions of mean and variance are analogous to those for a weighted set of points in Euclidean space, but with the underlying space being the space of phylogenetic trees constructed by Billera, Holmes, and Vogtmann (2001). A property of this space (non-positive curvature) ensures there is a unique shortest path between any two trees. Furthermore, this path can be computed in polynomial time, leading to a practical algorithm for computing the mean and variance.  I will compare the mean and variance to existing consensus tree and summary methods, as well as present applications to such biological problems as the reconstruction of phylogenetic trees and the automatic labeling of lung airway scans.