2019-2020 Seminars

Dec
10
2019

Computer Science/Discrete Mathematics Seminar II

Graph removal lemmas
10:30am|Simonyi Hall 101

Continuing last week's lecture, among the numerous applications of the regularity lemma, a classical one is the graph removal lemma. It has applications in fields such as number theory and theoretical computer science. For every fixed graph H, the H...

Dec
09
2019

Computer Science/Discrete Mathematics Seminar I

Graph Sparsification via Short Cycle Decomposition
11:00am|Simonyi Hall 101

We develop a framework for graph sparsification and sketching, based on a new tool, short cycle decomposition -- a decomposition of an unweighted graph into an edge-disjoint collection of short cycles, plus a small number of extra edges. A simple...

Dec
04
2019

Theoretical Machine Learning Seminar

Uncoupled isotonic regression
12:00pm|Dilworth Room

The classical regression problem seeks to estimate a function f on the basis of independent pairs $(x_i,y_i)$ where $\mathbb E[y_i]=f(x_i)$, $i=1,\dotsc,n$. In this talk, we consider statistical and computational aspects of the "uncoupled" version...

Dec
03
2019

Computer Science/Discrete Mathematics Seminar II

Regularity lemma and its applications Part I
10:30am|Simonyi Hall 101

Szemeredi's regularity lemma is an important tool in modern graph theory. It and its variants have numerous applications in graph theory, which in turn has applications in fields such as theoretical computer science and number theory. The first part...

Dec
02
2019

Computer Science/Discrete Mathematics Seminar I

Rainbow fractional matchings
Ron Holzman
11:00am|Simonyi Hall 101

Given a family of m matchings in a graph G (where each matching can be thought of as a color class), a rainbow matching is a choice of edges of distinct colors that forms a matching. How many matchings of size n are needed to guarantee the existence...

Nov
26
2019

Theoretical Machine Learning Seminar

A Fourier Analysis Perspective of Training Dynamics of Deep Neural Networks
11:30am|White-Levy

This talk focuses on a general phenomenon of "Frequency-Principle" that DNNs often fit target functions from low to high frequencies during the training. I will present empirical evidences on real datasets and deep networks of different settings as...

Nov
26
2019

Computer Science/Discrete Mathematics Seminar II

Constraint Satisfaction Problems and Probabilistic Combinatorics II
Fotios Illiopoulos
10:30am|Simonyi Hall 101

The tasks of finding and randomly sampling solutions of constraint satisfaction problems over discrete variable sets arise naturally in a wide variety of areas, among them artificial intelligence, bioinformatics and combinatorics, and further have...

Nov
25
2019

Computer Science/Discrete Mathematics Seminar I

Lifting small locally testable codes (LTCs) to large LTCs via HDXs
Prahladh Harsha
11:00am|Simonyi Hall 101

In this talk, I'll illustrate how to lift a "small" locally testable code via a high dimensional expander (HDX) to a "large" locally testable code. Given a D-left regular bipartite graph G = ([n], [m], E) and a "small" code C \in {0,1}^D, the Tanner...

Nov
20
2019

Theoretical Machine Learning Seminar

Nonconvex Minimax Optimization
12:00pm|Dilworth Room

Minimax optimization, especially in its general nonconvex formulation, has found extensive applications in modern machine learning, in settings such as generative adversarial networks (GANs) and adversarial training. It brings a series of unique...

Nov
19
2019

Computer Science/Discrete Mathematics Seminar II

Constraint Satisfaction Problems and Probabilistic Combinatorics I
Fotios Illiopoulos
10:30am|Simonyi Hall 101

The tasks of finding and randomly sampling solutions of constraint satisfaction problems over discrete variable sets arise naturally in a wide variety of areas, among them artificial intelligence, bioinformatics and combinatorics, and further have...