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.
2018 Jan 29

NT&AG: Shachar Carmeli (Weizmann Institute), "Higher Etale Obstructions for Quadratic Forms"

2:00pm to 3:00pm

Location:

Room 70A, Ross Building, Jerusalem, Israel
2018 Jan 24

Analysis Seminar: T. Umeda "Space-time estimates for strongly propagative systems: From Maxwell to Dirac equations"

12:00pm to 1:00pm

Location:

Room 70, Ross building
2018 Jan 17

Jerusalem Analysis Seminar - Avner Kiro (TAU) "On Taylor coefficients of smooth functions."

12:00pm to 1:00pm

2017 Dec 05

T&G: Michael Farber (IIAS), Robot motion planning and Bredon equivariant cohomology

12:00pm to 1:30pm

Location:

Room 70A, Ross Building, Jerusalem, Israel
I will describe a topological approach to the robot motion planning problem focusing mainly on the case of aspherical configuration spaces.
2018 Jan 29

HD-Combinatorics Special day: Pseudo-randomness (organised by Uli Wagner)

10:00am to 5:00pm

Location:

IIAS, Feldman Building, Givat Ram
10:00-11:00     Anna Gundert Uli Wagner - Quasirandomness and expansion for graphs

11:30-12:30     Anna Gundert Uli Wagner - Quasirandomness for hypergraphs

13:45- 14:45    Uli Wagner - Szemeredi's regularity lemma for dense graphs

15:00-16:00     Tamar Ziegler - Gowers uniformity norms

16:30-17:30     Anna Gundert Uli Wagner - Hypergraph regularity
2018 Feb 12

HD-Combinatorics Special day: High Dim Random Walks (organised by Ron Rosenthal)

(All day)

Location:

IIAS, Feldman Building, Givat Ram
2018 Jan 14

Game Theory & Math Economics: Harry Dankowicz (UIUC) "Emergent Task Differentiation on Network Filters"

4:00pm to 4:30pm

Location:

Elath Hall, 2nd floor, Feldman Building, Edmond J. Safra Campus
Inspired by empirical observations on honey bee colonies, we analyze the emergence of task differentiation in a model complex system, characterized by an absence of hierarchical control, yet able to exhibit coordinated behavior and collective function. The analysis considers the steady-state response of a mechanical interaction network to exogenous resonant excitation.
2017 Dec 24

Game Theory & Math Economics: Yonatan Aumann (Bar - Ilan) - "On Time Discounting, Impatience and Risk Aversion"

4:00pm to 4:30pm

Location:

Elath Hall, 2nd floor, Feldman Building, Edmond J. Safra Campus
Time discounting is a ubiquitous assumption in economic literature. We (re)explore the foundations of such time preferences. "Impatience" is defined as a preferences for experiencing the better states sooner rather than later, even when there is no uncertainty associated with the future. We show that, assuming consistency and some weak stationarity assumptions, impatience is incompatible with a meaningful notion of a risk-attitude (risk aversion/love/neutrality).On the other hand, if there is uncertainty associated with the future then discounting necessarily emerges.