[Colloquium] REMINDER: 8/7 TTIC Colloquium: Aravindan Vijayaraghavan, Northwestern University

[Mary Marre via Colloquium]

When:     Monday, August 7th at 11:00 a.m.

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

Who:       Aravindan Vijayaraghavan, Northwestern University


Title:       Learning Mixtures of Well-Separated Gaussians

Abstract:
Mixtures of spherical Gaussians are among the most widely used statistical
models for clustering. We will consider the problem of efficiently learning
a mixture of a large number of spherical Gaussian components, when the
components of the mixture are well-separated. Here, we are given samples
from a mixture of k spherical Gaussians with parameters corresponding to
the means, variances and mixing weights for each of the components. The
goal is to estimate the parameters up to accuracy \delta using \poly(k,d,
1/\delta) samples.

There is a significant gap between the best known upper bounds and lower
bounds in the amount of separation required for efficiently learning a
mixture of k spherical Gaussians. We will consider the following question:
what is the minimum order of separation needed for learning a mixture of
spherical Gaussians with polynomial samples?

In this talk, I will give a new iterative algorithm for learning mixtures
of k spherical Gaussians, and give sample complexity lower bounds that
together essentially characterize the optimal order of separation between
components that is needed to learn a mixture of k spherical Gaussians with
polynomial samples.

This is based on joint work with Oded Regev.



Host:  <yury at ttic.edu>Yury Makarychev <yury at ttic.edu>


For more information on the colloquium series or to subscribe to the
mailing list, please see http://www.ttic.edu/colloquium.php


Mary C. Marre
Administrative Assistant
*Toyota Technological Institute*
*6045 S. Kenwood Avenue*
*Room 504*
*Chicago, IL  60637*
*p:(773) 834-1757*
*f: (773) 357-6970*
*mmarre at ttic.edu <mmarre at ttic.edu>*

On Sun, Aug 6, 2017 at 5:27 PM, Mary Marre <mmarre at ttic.edu> wrote:

> When:     Monday, August 7th at 11:00 a.m.
>
> Where:    TTIC, 6045 S. Kenwood Avenue, 5th Floor, Room 526
>
> Who:       Aravindan Vijayaraghavan, Northwestern University
>
>
> Title:       Learning Mixtures of Well-Separated Gaussians
>
> Abstract:
> Mixtures of spherical Gaussians are among the most widely used statistical
> models for clustering. We will consider the problem of efficiently learning
> a mixture of a large number of spherical Gaussian components, when the
> components of the mixture are well-separated. Here, we are given samples
> from a mixture of k spherical Gaussians with parameters corresponding to
> the means, variances and mixing weights for each of the components. The
> goal is to estimate the parameters up to accuracy \delta using \poly(k,d,
> 1/\delta) samples.
>
> There is a significant gap between the best known upper bounds and lower
> bounds in the amount of separation required for efficiently learning a
> mixture of k spherical Gaussians. We will consider the following
> question: what is the minimum order of separation needed for learning a
> mixture of spherical Gaussians with polynomial samples?
>
> In this talk, I will give a new iterative algorithm for learning mixtures
> of k spherical Gaussians, and give sample complexity lower bounds that
> together essentially characterize the optimal order of separation between
> components that is needed to learn a mixture of k spherical Gaussians with
> polynomial samples.
>
> This is based on joint work with Oded Regev.
>
>
>
> Host:  <yury at ttic.edu>Yury Makarychev <yury at ttic.edu>
>
>
> For more information on the colloquium series or to subscribe to the
> mailing list, please see http://www.ttic.edu/colloquium.php
>
>
> Mary C. Marre
> Administrative Assistant
> *Toyota Technological Institute*
> *6045 S. Kenwood Avenue*
> *Room 504*
> *Chicago, IL  60637*
> *p:(773) 834-1757 <(773)%20834-1757>*
> *f: (773) 357-6970 <(773)%20357-6970>*
> *mmarre at ttic.edu <mmarre at ttic.edu>*
>
> On Mon, Jul 31, 2017 at 3:33 PM, Mary Marre <mmarre at ttic.edu> wrote:
>
>> When:     Monday, August 7th at 11:00 a.m.
>>
>> Where:    TTIC, 6045 S. Kenwood Avenue, 5th Floor, Room 526
>>
>> Who:       Aravindan Vijayaraghavan, Northwestern University
>>
>>
>> Title:       Learning Mixtures of Well-Separated Gaussians
>>
>> Abstract:
>> Mixtures of spherical Gaussians are among the most widely used
>> statistical models for clustering. We will consider the problem of
>> efficiently learning a mixture of a large number of spherical Gaussian
>> components, when the components of the mixture are well-separated. Here, we
>> are given samples from a mixture of k spherical Gaussians with parameters
>> corresponding to the means, variances and mixing weights for each of the
>> components. The goal is to estimate the parameters up to accuracy \delta
>> using \poly(k,d, 1/\delta) samples.
>>
>> There is a significant gap between the best known upper bounds and lower
>> bounds in the amount of separation required for efficiently learning a
>> mixture of k spherical Gaussians. We will consider the following
>> question: what is the minimum order of separation needed for learning a
>> mixture of spherical Gaussians with polynomial samples?
>>
>> In this talk, I will give a new iterative algorithm for learning mixtures
>> of k spherical Gaussians, and give sample complexity lower bounds that
>> together essentially characterize the optimal order of separation between
>> components that is needed to learn a mixture of k spherical Gaussians with
>> polynomial samples.
>>
>> This is based on joint work with Oded Regev.
>>
>>
>>
>> Host:  <yury at ttic.edu>Yury Makarychev <yury at ttic.edu>
>>
>>
>>
>>
>> For more information on the colloquium series or to subscribe to the
>> mailing list, please see http://www.ttic.edu/colloquium.php
>>
>>
>>
>>
>>
>> Mary C. Marre
>> Administrative Assistant
>> *Toyota Technological Institute*
>> *6045 S. Kenwood Avenue*
>> *Room 504*
>> *Chicago, IL  60637*
>> *p:(773) 834-1757 <(773)%20834-1757>*
>> *f: (773) 357-6970 <(773)%20357-6970>*
>> *mmarre at ttic.edu <mmarre at ttic.edu>*
>>
>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mailman.cs.uchicago.edu/pipermail/colloquium/attachments/20170807/a17bbf61/attachment-0001.html>