All talks will be given by Amnon Ta-Shma. 10:00-11:00 - The sampling problem and some equivalent formulations
11:30-12:30 - A basic "combinatorial" construction
14:00-14:45 - Algebraic constructions of randomness condensers
15:15-16:00 - Structured sampling
Program:
1. 10:00-11:00 - The sampling problem and some equivalent formulations. Abstract: We will first define Samplers, and the parameters that one usually tries to optimize: accuracy, confidence, query complexity
Abstract: We describe some different techniques for studying cohomology (both rationally and integrally), including the idea of studying "towers" (of spaces or groups).
Examples include the circle, the Alexander polynomial of a knot, and arithmetic groups.
Manchester Building (Hall 2), Hebrew University Jerusalem
Additive combinatorics enable one to characterize subsets S of elements in a group such that S+S has small cardinality. We are interested in linear analogues of these results, namely characterizing subspaces S in some algebras (mostly extension fields) such that the linear span of the set S^2 of products st, for s,t in S, has small dimension. We shall present a linear analogue of a theorem of Vosper which says that under the right conditions, a sufficiently small dimension for S^2 implies that S has a basis of elements in geometric progression.
Real and complex Monge-Ampere equations play a central role in several
branches of geometry and analysis. We introduce a quaternionic version
of a Monge-Ampere equation which is an analogue of the famous Calabi
problem in the complex case. It is a non-linear elliptic equation of second
order on so called HyperKahler with Torsion (HKT) manifolds (the latter
manifolds were introduced by physicists in 1990's). While in full generality
it is still unsolved, we will describe its solution in a special case and some
Topic: Limits of Correlation with Bounded Complexity
Abstract:
Peretz (2013) showed that, perhaps surprisingly, players whose recall is bounded can correlate in a long repeated game against a player of greater recall capacity. We show that correlation is already impossible against an opponent whose recall capacity is only linearly larger. This result closes a gap in the characterisation of min-max levels, and hence also equilibrium payoffs, of repeated games with bounded recall.
This paper characterizes the ordinal utilities over the bounded infinite streams of payoffs that satisfy the time-value of money principle and an additivity property, and those that in addition are impatient. Building on this characterization, the paper introduces the concept of optimization that is robust to small imprecision in the specification of the preference, and proves that the set of feasible streams of payoffs of a finite Markov Decision Process admits such a robust optimization.
A sound legal infrastructure is critical to the development of the Israeli economy. In its absence, business people and private persons alike face difficulties in planning their actions. All too often they are obliged to turn to the courts of law. However, in the absence of a proper infrastructure, those do not themselves have the necessary tools to resolve the disputes. The matters at issue are not marginal. They have long-lasting consequences for the economy. The number of publicly-traded companies listed in Tel-Aviv Stock Exchange sank from 657 in 2008 to 461 in March 2016.
Topic: Calibrated Forecasts, Leaks, and Game Equilibria (joint work with Dean P. Foster)
Place: Elath Hall, 2nd floor, Feldman Building, Edmond Safra Campus
Time: Sunday, November 22, 2015 at 4:00 p.m.
Refreshments available at 3:30 p.m.
YOU ARE CORDIALLY INVITED
Topic: Has the National Health Insurance Law Run its Course?
Place: Elath Hall, 2nd floor, Feldman Building, Edmond Safra Campus
Time: Sunday, June 19, 2016 at 4:00 p.m.
Refreshments available at 3:30 p.m.
YOU ARE CORDIALLY INVITED
Abstract:
The National Health Insurance Law is operated through several economic mechanisms that are meant to implement its vision.
In this lecture we will present the main flaws of some of these mechanisms and propose ways to fix them. The lecture will be in hebrew.
Speaker: Liad Blumrosen, HUJI
Topic: (Almost) Efficient Mechanisms for Bilateral Trading (joint work with Shahar Dobzinski)
Place: Elath Hall, 2nd floor, Feldman Building, Edmond Safra Campus
Time: Sunday, November 15, 2015 at 4:00 p.m.
Refreshments available at 3:30 p.m.
YOU ARE CORDIALLY INVITED