[Colloquium] Research at TTIC: Tamir Hazan

[Liv Leader]

REMINDER:

When:     Friday, October 12th at Noon

Where:    TTIC, 6045 S Kenwood Avenue, 5th Floor, Room #526

Who:      Tamir Hazan

Title:       Inference and Learning with Random Maximum A-Posteriori
Perturbations

Abstract:
Inference involves assessing the weights of possible structures, whether
objects, parsers, or molecular structures. Although it is often feasible to
only find the most likely or maximum a-posteriori (MAP) assignment rather
than considering all possible assignment, MAP inference is limited when
there are other likely assignments. In a fully probabilistic treatment, all
possible alternative assignments are considered thus requiring summing over
the assignments with their respective weights  which is considerably harder
(#P hard vs NP hard). The main surprising result of our work is that MAP
inference (maximization) can be used to approximate and bound the weighted
counting. This leads us to a new approximate inference framework that is
based on MAP-statistics, thus does not depend on pseudo-probabilities,
contrasting the current framework of Bethe approximations which lacks
statistical meaning. This approach excels in regimes where there are
several but not exponentially many prominent assignments. For example, this
happens in cases where observations carry strong signals (local evidence)
but are also guided by strong consistency constraints (couplings).


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Research at TTIC Seminar Series

TTIC is hosting a weekly seminar series presenting the research currently
underway at the Institute. Every week a different TTIC faculty member will
present their research.  The lectures are intended both for students
seeking research topics and adviser, and for the general TTIC and
University of Chicago communities interested in hearing what their
colleagues are up to.

To receive announcements about the seminar series, please subscribe to the
mailing list: https://groups.google.com/a/ttic.edu/group/talks/subscribe

Speaker details can be found at: http://www.ttic.edu/tticseminar.php.

For additional questions, please contact Nati Srebro at nati at ttic.edu.


-- 
Liv Leader
Director of Human Resources and International Affairs

Toyota Technological Institute Chicago
6045 S Kenwood Ave
Chicago, IL 60637
Phone- (773) 702-5033
Fax-     (773) 834-9881
Email-  lleader at ttic.edu
Web-   www.ttic.edu
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