Department of Computer Science | Institute of Theoretical Computer Science | CADMO

Theory of Combinatorial Algorithms

Prof. Emo Welzl and Prof. Bernd Gärtner

Mittagsseminar (in cooperation with M. Ghaffari, A. Steger and B. Sudakov)

Mittagsseminar Talk Information

Date and Time: Tuesday, September 25, 2007, 12:15 pm

Duration: This information is not available in the database

Location: CAB G51

Speaker: Rico Zenklusen

High-Confidence Estimation of Small s-t Reliabilities in Acyclic Networks

In the classical s-t network reliability problem a fixed network G is given including two designated vertices s and t (called terminals). The edges are subject to independent random failure, and the task is to compute the probability that s and t a re connected in the resulting network, which is known to be #P-complete. In this talk, I will discuss the issue of approximating the s-t reliability in case of a directed acyclic original network G. A specialized version of a Monte-Carlo algorithm given by Karp and Luby will be introduced and analyzed. For the case of uniform edge failure probabilities, I will present a worst-case bound on the number of samples that have to be drawn to obtain an epsilon-delta approximation, being sharper than the original upper bound. Computational results on two types of random networks (directed acyclic Delaunay graphs and a slightly modified version of a classical random graph) with up to one million vertices are presented. These results show the advantage of the introduced Monte-Carlo approach compared to direct simulation when small reliabilities have to be estimated and demonstrate its applicability on large-scale instances. Furthermore, applications to spreading processes on networks will be highlighted.

Joint work with Marco Laumanns.

Upcoming talks     |     All previous talks     |     Talks by speaker     |     Upcoming talks in iCal format (beta version!)

Previous talks by year:   2018  2017  2016  2015  2014  2013  2012  2011  2010  2009  2008  2007  2006  2005  2004  2003  2002  2001  2000  1999  1998  1997  1996  

Information for students and suggested topics for student talks

Automatic MiSe System Software Version 1.4803M   |   admin login