2022-2023 Seminars

Dec
12
2022

Computer Science/Discrete Mathematics Seminar I

Optimization-Friendly Generic Mechanisms Without Money
11:15am|Simonyi 101 and Remote Access

Our goal is to develop a generic framework for converting modern gradient-descent based optimization algorithms into mechanisms where inputs come from self-interested agents.

We focus on aggregating preferences from n players in a context without...

Dec
06
2022

Computer Science/Discrete Mathematics Seminar II

Online List Labeling: Breaking the log$^2$ n Barrier
Nicole Wein
10:30am|Simonyi Hall 101 and Remote Access

The online list labeling problem is a basic primitive in data structures. The goal is to store a dynamically-changing set of n items in an array of m slots, while keeping the elements in sorted order. To do so, some items may need to be moved over...

Dec
05
2022

Computer Science/Discrete Mathematics Seminar I

Optimal Weak to Strong Learning
Kasper Green Larsen
11:15am|Simonyi 101 and Remote Access

The classic algorithm AdaBoost allows to convert a weak learner, that is an algorithm that produces a hypothesis which is slightly better than chance, into a strong learner, achieving arbitrarily high accuracy when given enough training data. We...

Nov
29
2022

Computer Science/Discrete Mathematics Seminar II

The Hypergraph Container Method, Partition Containers, and Algorithmic Applications
10:30am|Simonyi Hall 101 and Remote Access

The recently-discoverd Hypergraph Container Method (Saxton and Thomason, Balogh, Morris and Samotij), generalizing an earlier version for graphs (Kleitman and Winston), is used extensively in recent years in extremal and probabilistic combinatroics...

Nov
28
2022

Computer Science/Discrete Mathematics Seminar I

Algorithmic Stochastic Localization for the Sherrington-Kirkpatrick Model
11:15am|Simonyi Hall 101 and Remote Access

Sampling from high-dimensional, multimodal distributions is a computationally challenging and fundamental task.  This talk will focus on a family of random instances of such problems described by random quadratic potentials on the hypercube known as...

Nov
22
2022

Computer Science/Discrete Mathematics Seminar II

The Polynomial Method in Communication Complexity
10:30am|Simonyi Hall 101 and Remote Access

A powerful technique developed and extended in the past decade in communication complexity is the so-called "lifting theorems."  The idea is to translate the hardness results from "easier" models, e.g., query complexity, polynomial degrees, to the...

Nov
21
2022

Computer Science/Discrete Mathematics Seminar I

Strong XOR Lemma for Communication with Bounded Rounds
Huacheng Yu
11:15am|Simonyi 101 and Remote Access

In this talk, we show a strong XOR lemma for bounded-round two-player randomized communication.  For a function f:X×Y→{0,1}, the n-fold XOR function f^⊕n:X^n×Y^n→{0,1} maps n input pairs (x_1,...,x_n), (y_1,...,y_n) to the XOR of the n output bits f...

Nov
15
2022

Computer Science/Discrete Mathematics Seminar II

10:30am|Simonyi Hall 101 and Remote Access

In this talk I will first review some basics about communication complexity.  Secondly I will survey some (old and new) equivalences between central problems in communication complexity and related questions in additive combinatorics.  In particular...

Nov
14
2022

Computer Science/Discrete Mathematics Seminar I

Communication and Query Complexity of Bipartite Perfect Matching
Yuval Efron
11:15am|Simonyi 101 and Remote Access

In this talk, I'll discuss a recent result where we settle the complexities of the maximum-cardinality bipartite matching problem (BMM) up to poly-logarithmic factors in five models of computation:  The two-party communication, AND query, OR query...

Nov
08
2022

Computer Science/Discrete Mathematics Seminar II

Introduction to Natural Quasirandomness: Unique Colorability and Orderability
10:30am|Simonyi Hall 101 and Remote Access

The theory of graph quasirandomness studies sequences of graphs that "look like" samples of the Erdős--Rényi random graph. The upshot of the theory is that several ways of comparing a sequence with the random graph turn out to be equivalent. For...