2018
Mar
12

# Events & Seminars

2018
Mar
22

2017
Nov
21

# T&G: Semyon Alesker (Tel Aviv University), Calabi type problem for Monge-Ampere equations on HKT manifolds

12:00pm to 1:30pm

## Location:

Room 70A, Ross Building, Jerusalem, Israel

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

2015
Dec
20

2016
Jan
10

# Game Theory & Math Economics: Francis Bloch (Paris School of Economics) - "Dynamic assignment of objects to queuing agents"

4:00pm to 5:00pm

## Location:

Elath Hall, 2nd floor, Feldman Building, Edmond Safra Campus

This paper analyzes the optimal assignment of objects which arrive sequentially to agents organized in a waiting list. Applications include the assignment of social housing and organs for transplants. We analyze the optimal design of probabilistic queuing disciplines, punishment schemes, the optimal timing of applications and information releases. We consider three efficiency criteria: the vector of values of agents in the queue, the probability of misallocation and the expected waste.

2016
May
08

# Game Theory & Math Economics: Matthew Elliott (Caltech) - "Endogenous Financial Networks: Efficient Modularity and Why Shareholders Prevent It" (joint work with Jonathon Hazell)

4:00pm to 5:00pm

## Location:

Elath Hall, 2nd floor, Feldman Building, Edmond Safra Campus

Topic: Endogenous Financial Networks: Efficient Modularity and Why Shareholders Prevent It (joint work with Jonathon Hazell) We consider systemic risk in financial networks, by examining the conflict of interest between debt- and equity-holders. Through trading, banks can diversify their idiosyncratic risks and avoid failures following small shocks. However, the resulting interdependencies can cause multiple failures after large shocks.

2015
Nov
15

# Game Theory & Math Economics: Liad Blumrosen (HUJI) - "(Almost) Efficient Mechanisms for Bilateral Trading" (joint work with Shahar Dobzinski)

3:30pm to 4:30pm

## Location:

Elath Hall, 2nd floor, Feldman Building, Edmond Safra Campus

We study the simplest form of two-sided markets: one seller, one buyer and a single item for sale. It is well known that there is no fully-efficient mechanism for this problem that maintains a balanced budget. We characterize the quality of the most efficient mechanisms that are budget balanced, and design simple and robust mechanisms with these properties. We also show how minimal use of statistical data can yield good results. Finally, we demonstrate how solutions for this simple bilateral-trade problem can be used as a "black-box" for constructing mechanisms in more general environments.

2016
May
29

# Game Theory & Math Economics: Eilon Solan (Tel Aviv University) - "Acceptable Strategy Profiles in Stochastic Games"

4:00pm to 5:00pm

## Location:

Elath Hall, 2nd floor, Feldman Building, Edmond Safra Campus

I will present a new solution concept for multiplayer stochastic games, namely, acceptable strategy profiles. For each player \(i\) and state \(s\) in a stochastic game, let \(w_i(s)\) be a real number.

2015
Nov
29

# Game Theory & Math Economics: Ran Spiegler (Tel Aviv University and University College London) - "On the "Limited Feedback" Foundation of Boundedly Rational Expectations"

4:00pm to 5:00pm

## Location:

Elath Hall, 2nd floor, Feldman Building, Edmond Safra Campus

A common justification for boundedly rational expectations is that agents receive partial feedback about the equilibrium distribution. I formalize this idea in the context of the "Bayesian network" representation of boundedly rational expectations, presented in Spiegler (2015). According to this representation, the decision maker forms his beliefs as if he Öts a subjective causal model - captured by a directed acyclic graph (DAG) over the set of variables - to the objective distribution.

2015
Dec
27

# Game Theory & Math Economics: Eyal Winter (HUJI) - "Rule Rationality" (Joint work with Yuval Heller)

4:00pm to 5:00pm

## Location:

Elath Hall, 2nd floor, Feldman Building, Edmond Safra Campus

We study the strategic advantages of following rules of thumb that bundle different games together (called rule rationality) when this may be observed by one’s opponent. We present a model in which the strategic environment determines which kind of rule rationality is adopted by the players. We apply the model to characterize the induced rules and outcomes in various interesting environments. Finally, we show the close relations between act rationality and “Stackelberg stability” (no player can earn from playing first). Refreshments available at 3:30 p.m.

2016
Mar
20

# Game Theory & Math Economics: Gilad Bavly and Ron Peretz (Bar-Ilan) - "Limits of Correlation with Bounded Complexity"

4:00pm to 5:00pm

## Location:

Elath Hall, 2nd floor, Feldman Building, Edmond Safra Campus

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.

2015
Nov
01

# Game Theory & Math Economics: Abraham Neyman (HUJI) - "Additive valuations of streams of payoffs that obey the time-value of money principle: Characterization and robust optimization"

4:00pm to 5:00pm

## Location:

Elath Hall, 2nd floor, Feldman Building, Edmond Safra Campus

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.

2016
May
15

# Game Theory & Math Economics: Talia Einhorn (Tel Aviv University & Ariel University) - "Israel's Legal Infrastructure – walking on thin ice"

4:00pm to 5:00pm

## Location:

Elath Hall, 2nd floor, Feldman Building, Edmond Safra Campus

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.

2015
Nov
22

# Game Theory & Math Economics: Sergiu Hart (HUJI) - "Calibrated Forecasts, Leaks, and Game Equilibria" (joint work with Dean P. Foster)

4:00pm to 5:00pm

## Location:

Elath Hall, 2nd floor, Feldman Building, Edmond Safra Campus

How good is a forecaster? Assume for concreteness that every day the forecaster issues a forecast of the type "the chance of rain tomorrow is 30%." A simple test one may conduct is to calculate the proportion of rainy days out of those days that the forecast was 30%, and compare it to 30%; and do the same for all other forecasts. A forecaster is said to be _calibrated_ if, in the long run, the differences between the actual proportions of rainy days and the forecasts are small—no matter what the weather really was.

2016
Jun
19

# Game Theory & Math Economics: Jacob (Kobi) Glazer (Tel Aviv University) - "Has the National Health Insurance Law Run its Course?"

4:00pm to 5:00pm

## Location:

Elath Hall, 2nd floor, Feldman Building, Edmond Safra Campus

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.