# Recently Added

## Leon Levy Lecture - Mass Higher Education and the Dropout Problem

Paul Atewell, Leon Levy Foundation Member, School of Social Science. In the United States, ever-increasing proportions of high school graduates continue into college, and more and more undergraduates continue into master’s programs. One concern with educational expansion is that many students do not complete their degrees; they “drop out.” Some read this as proof that too many students are going to college, but other scholars argue that not enough Americans are receiving degrees. In this talk, Paul Attewell, Professor of Sociology at the Graduate Center of the City University of New York, will consider the reasons behind the dropout phenomenon, examining individual factors but also highlighting government policies and institutional practices that undercut students’ progress toward graduation.

## Measuring Shape With Homology

The ordinary homology of a subset S of Euclidean space depends only on its topology. By systematically organizing homology of neighborhoods of S, we get quantities that measure the shape of S, rather than just its topology. These quantities can be used to define a new notion of fractional dimension of S. They can also be effectively calculated on a computer.

## Mobius Randomness and Dynamics

## Compressing Bounded-Round Communication

## A Combinatorial Proof of the Chernoff-Hoeffding Bound, With Applications to Direct-Product Theorems

We give a simple combinatorial proof of the Chernoff-Hoeffding concentration

bound for sums of independent Boolean random variables. Unlike the standard

proofs, our proof does not rely on the method of higher moments, but rather uses

an intuitive counting argument. In addition, this new proof is constructive in the

following sense: if the given random variables fail the concentration bound, then

we can efficiently find a subset of the variables that are statistically dependent.

## Product Rules in Semidefinite Programming

## Pseudorandom Generators for Regular Branching Programs

We shall discuss new pseudorandom generators for regular read-once branching programs of small width. A branching program is regular if the in-degree of every vertex in it is (either 0 or) 2. For every width d and length n, the pseudorandom generator uses a seed of length $O((log d + log log n + log(1/p)) log n)$ to produce $n$ bits that cannot be distinguished from a uniformly random string by any regular width $d$ length $n$ read-once branching program, except with probability $p > 0$

## Extremal Problems for Convex Lattice Polytopes

In this survey I will present several extremal problems, and some solutions, concerning convex lattice polytopes.

A typical example is to determine the smallest area that a convex lattice polygon can have if it has exactly n vertices.

## Edward T. Cone Concert Talk

Jazz journalist Nate Chinen, who writes for the *New York Times*, the *Village Voice*, and *JazzTimes*, is joined by pianists Vijay Iyer and Craig Taborn, along with Institute Artist-in-Residence, for a conversation about improvisational jazz and performance.