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IMA Newsletter #422

December 2011

2011-2012 Program

See http://www.ima.umn.edu/2011-2012/ for a full description of the 2011-2012 program on Mathematics of Information.

Schedule

Thursday, December 1

2:30pm-3:00pm Coffee breakLind Hall 400

Friday, December 2

1:25pm-2:25pm Using POMDPs to understand and support human sequential decision making with uncertaintyBrian J. Stankiewicz (3M)Lind Hall 305 IPS
2:30pm-3:00pm Coffee breakLind Hall 400

Monday, December 5

2:30pm-3:00pm Coffee breakLind Hall 400

Tuesday, December 6

11:15am-12:15pm Sparse coding and object recognition Arthur Szlam (University of Minnesota)Lind Hall 305 PS
2:30pm-3:00pm Coffee breakLind Hall 400

Wednesday, December 7

2:30pm-3:00pm Coffee breakLind Hall 400

Thursday, December 8

2:30pm-3:00pm Coffee breakLind Hall 400

Friday, December 9

2:30pm-3:00pm Coffee breakLind Hall 400

Monday, December 12

2:30pm-3:00pm Coffee breakLind Hall 400

Tuesday, December 13

11:15am-12:15pm Derivatives of eigenvalue functionsBrendan P.W. Ames (University of Minnesota)Lind Hall 401 PS
2:30pm-3:00pm Coffee breakLind Hall 400

Wednesday, December 14

2:30pm-3:00pm Coffee breakLind Hall 400

Thursday, December 15

2:30pm-3:00pm Coffee breakLind Hall 400

Friday, December 16

2:30pm-3:00pm Coffee breakLind Hall 400

Monday, December 19

2:30pm-3:00pm Coffee breakLind Hall 400

Tuesday, December 20

2:30pm-3:00pm Coffee breakLind Hall 400

Wednesday, December 21

2:30pm-3:00pm Coffee breakLind Hall 400

Thursday, December 22

2:30pm-3:00pm Coffee breakLind Hall 400

Friday, December 23

2:30pm-3:00pm Coffee breakLind Hall 400

Monday, December 26

All Day Christmas Day (observed). The IMA is closed.

Tuesday, December 27

All Day University Holiday. The IMA is closed.

Wednesday, December 28

2:30pm-3:00pm Coffee breakLind Hall 400

Thursday, December 29

2:30pm-3:00pm Coffee breakLind Hall 400

Friday, December 30

2:30pm-3:00pm Coffee breakLind Hall 400

Event Legend:

IPSIndustrial Problems Seminar
PSIMA Postdoc Seminar
Abstracts
Brendan P.W. Ames (University of Minnesota) Derivatives of eigenvalue functions
Abstract: The eigenvalues of a symmetric operator play a significant role in many areas of mathematics and engineering. As such, it is important to understand the behaviour of the spectrum of a matrix under small perturbations. This talk is divided into two parts. In the first, I will review several important results from the literature regarding the sensitivity of the eigenvalues of a symmetric matrix. In particular, I will provide formulas for the directional derivatives of the spectrum of a symmetric matrix, and discuss how these formulas can be extended to obtain a series approximation of the spectrum of a symmetric matrix under small perturbations. The second half of the talk will focus on the sensitivity of functions of the spectrum of a symmetric matrix. If F(X) is a function that depends smoothly on the eigenvalues of X, I will provide conditions for when this smoothness is inherited by F. As examples, I will provide conditions for differentiability of spectral functions and primary matrix functions, as well as formulas for their gradients.
Brian J. Stankiewicz (3M) Using POMDPs to understand and support human sequential decision making with uncertainty
Abstract: Humans possess the remarkable ability to make thousands of decision every day under conditions of incredible uncertainty. Furthermore the outcomes of a decisions may not be felt for hours, days, weeks or even years and there may even have been many decisions made before there is any cost or reward generated. Developing a robust decision making system for these conditions remains a computational challenge due to the combinatoric nature of these problem along with being able to dynamically formulate an estimate of the system. However, you and I do it every day hundreds if not thousands of times. Thus we remain existence proof that such a computational system can exist. To better understand how humans accomplish this task we leverage the work in Partially Observable Markov Decision Processes (POMDPs) to provide us with a framework for providing optimal decision policies when making sequential decision under uncertainty. By comparing human performance to the optimal policy we have developed methods to dissect and identify which aspects of human cognition are optimal and sub-optimal. By identifying the computational strengths and limits of the human mind we can then identify the necessary computations to support and improve the human decision making process.
Arthur Szlam (University of Minnesota) Sparse coding and object recognition
Abstract: I will review a standard object recognition architecture, and discuss each of the components: SIFT features, sparse coding, pooling, and linear classifiers. I will then mention recent work of myself and collaborators on a fast version of this machine.
Visitors in Residence
Brendan P.W. Ames University of Minnesota 8/31/2011 - 8/30/2012
Bubacarr Bah University of Edinburgh 9/15/2011 - 12/15/2011
Arindam Banerjee University of Minnesota 9/1/2011 - 6/30/2012
Andrew John Beveridge Macalester College 9/1/2011 - 5/15/2012
Sergey G Bobkov University of Minnesota 9/1/2011 - 6/30/2012
Luca Capogna University of Minnesota 8/15/2011 - 6/10/2012
Aycil Cesmelioglu University of Minnesota 9/30/2010 - 8/30/2012
Paolo Codenotti University of Minnesota 9/1/2011 - 8/30/2012
Jintao Cui University of Minnesota 8/31/2010 - 8/30/2012
Isabel K. Darcy University of Iowa 9/1/2011 - 6/30/2012
Dainius Dzindzalieta Vilnius State University 9/1/2011 - 12/22/2011
Leonardo Espin NONE 9/1/2011 - 6/30/2012
Carlos Andres Garavito-Garzon University of Minnesota 9/8/2011 - 6/30/2012
Yulia Hristova University of Minnesota 9/1/2010 - 8/31/2012
Gilad Lerman University of Minnesota 9/1/2011 - 6/30/2012
Wenbo Li University of Delaware 9/1/2011 - 5/30/2012
Xin Liu University of Minnesota 8/31/2011 - 8/30/2012
Shiqian Ma University of Minnesota 8/31/2011 - 8/30/2013
Yu (David) Mao University of Minnesota 8/31/2010 - 8/30/2012
Gabriela Martínez University of Minnesota 8/31/2011 - 8/30/2013
Saurabh Mishra Eagan High School 8/22/2011 - 12/31/2011
Dimitrios Mitsotakis University of Minnesota 10/27/2010 - 8/31/2012
Luke Olson University of Illinois at Urbana-Champaign 9/1/2011 - 12/31/2011
Mary Therese Padberg University of Iowa 8/16/2011 - 1/31/2012
Candice Renee Price University of Iowa 8/1/2011 - 7/31/2012
Weifeng (Frederick) Qiu University of Minnesota 8/31/2010 - 8/30/2012
Guillermo R. Sapiro University of Minnesota 9/1/2011 - 5/31/2012
Brian J. Stankiewicz 3M 12/2/2011 - 12/2/2011
Arthur Szlam University of Minnesota 8/31/2011 - 8/30/2012
Jared Tanner University of Edinburgh 9/19/2011 - 12/5/2011
Divyanshu Vats University of Minnesota 8/31/2011 - 8/30/2012
Lan Wang University of Minnesota 9/1/2011 - 5/12/2012
Ke Wei University of Edinburgh 10/10/2011 - 12/10/2011
Elisabeth Werner Case Western Reserve University 9/1/2011 - 12/3/2011
Lingzhou Xue University of Minnesota 9/1/2011 - 6/30/2012
Ofer Zeitouni University of Minnesota 9/1/2011 - 12/9/2011
Teng Zhang University of Minnesota 8/31/2011 - 8/30/2012
Legend: Postdoc or Industrial Postdoc Long-term Visitor

IMA Affiliates:
Arizona State University, Boeing, Colorado State University, Corning Incorporated, ExxonMobil, Ford, General Motors, Georgia Institute of Technology, Honeywell, IBM, Indiana University, Iowa State University, Korea Advanced Institute of Science and Technology (KAIST), Lawrence Livermore National Laboratory, Lockheed Martin, Los Alamos National Laboratory, Medtronic, Michigan State University, Michigan Technological University, Mississippi State University, Northern Illinois University, Ohio State University, Pennsylvania State University, Portland State University, Purdue University, Rice University, Rutgers University, Sandia National Laboratories, Schlumberger Cambridge Research, Schlumberger-Doll, Seoul National University, Siemens, Telcordia, Texas A & M University, University of Central Florida, University of Chicago, University of Delaware, University of Houston, University of Illinois at Urbana-Champaign, University of Iowa, University of Kentucky, University of Maryland, University of Michigan, University of Minnesota, University of North Carolina, University of Notre Dame, University of Pennsylvania, University of Pittsburgh, University of Tennessee, University of Wisconsin-Madison, University of Wyoming, US Air Force Research Laboratory, Wayne State University, Worcester Polytechnic Institute, Zhejiang University