Max-Planck-Institut für Informatik
max planck institut
mpii logo Minerva of the Max Planck Society

MPI-INF or MPI-SWS or Local Campus Event Calendar

<< Previous Entry Next Entry >> New Event Entry Edit this Entry Login to DB (to update, delete)
What and Who
Title:On Rationality of Nonnegative Matrix Factorization
Speaker:James Worrell
coming from:University of Oxford
Speakers Bio:James Worrell is a Professor of Computer Science at the University of Oxford.  He currently holds on an EPSRC Established Career Fellowship on the subject of Verification of Linear Dynamical Systems.
Event Type:SWS Distinguished Lecture Series
Visibility:D1, D2, D3, D4, D5, SWS, RG1, MMCI
We use this to send out email in the morning.
Level:Expert Audience
Date, Time and Location
Date:Tuesday, 2 May 2017
Duration:60 Minutes
Building:E1 5
The nonnegative rank of a nonnegative m x n matrix M is the smallest number d such that M can be written as the product M = WH of a nonnegative m x d matrix W and a nonnegative d x n matrix H.  The notions of nonnegative rank and nonnegative matrix factorization have a wide variety of applications, including bioinformatics, computer vision, communication complexity, document clustering, and recommender systems. A longstanding open problem is whether, when M is a rational matrix, the factors W and H in a rank decomposition M=WH can always be chosen to be rational.  In this talk we resolve this problem negatively and discuss consequences of this result for the computational complexity of computing nonnegative rank.

This is joint work with Dmitry Chistikov, Stefan Kiefer, Ines Marusic, and Mahsa Shirmohammadi.

Name(s):Brigitta Hansen
Phone:0681 93039102
EMail:--email address not disclosed on the web
Video Broadcast
Video Broadcast:YesTo Location:Kaiserslautern
To Building:G26To Room:112
Meeting ID:
Tags, Category, Keywords and additional notes
Attachments, File(s):

Brigitta Hansen/MPI-SWS, 03/29/2017 02:28 PM
Last modified:
Uwe Brahm/MPII/DE, 05/02/2017 07:01 AM
  • Brigitta Hansen, 03/29/2017 02:31 PM -- Created document.