Webinar Series on Game Theory & Networks

Networks & Games Webinar Series
 

Networks & Games (www.gamesnet.in) presents a webinar series on Game Theory and Network Theory.


Lecture 24

Speaker: Encarna Algaba, Professor of Applied Mathematics, University of Seville

Venue: https://us02web.zoom.us/j/85495827377?pwd=M0hFZ1UyMXlyRW1FSEw5UllwUCtKQT09

Date: 28th April 2021 | Add to Google Calendar

Time: 7.30PM India Time

Duration: 1 hour

Title: Communication, Hierarchy, and Games with Restricted Cooperation

Abstract: Most of the network structures in the real world present features of communication and hierarchy. In fact, the different positions taken by a group of agents in some network structures are often determined by these properties. In this talk, we provide an overview of the most common models with communication or hierarchy restrictions in cooperative games and discuss network structures that combine both communication as well as hierarchical features. These network structures are illustrated by applying them to cooperative games with restricted cooperation.

Author Bio: Encarnación Algaba is Full Professor in the Department of Applied Mathematics II of the Advanced Engineering School at the University of Seville and research member in the Mathematics Research Institute of Seville University (IMUS). She also received her Ph.D. degree in Mathematical Sciences from the University of Seville. Her main research line is about Cooperative Games on Combinatorial Structures and their applications, with relevant contributions in the area. She is in the Editorial Board of Mathematics, and of Journal of Dynamics & Games. She has served as evaluator of projects at national and European level. She has organized diverse Streams of International Conferences and workshops on Game Theory. She has been invited speaker and guest researcher at various leading universities.

 

Lecture 23

Speaker: Ratul Lahkar, Professor of Economics, Ashoka University

Venue: https://us02web.zoom.us/j/83755796638?pwd=Nmp1SVF0ZlZBelAxQnVaclpjbCtTQT09

Date: 14th April 2021 | Add to Google Calendar

Time: 7.30PM India Time

Duration: 1 hour

Title: Affirmative Action in Large Population Contests

Abstract: We consider affirmative action in large population Tullock contests. The standard Tullock contest is an equal treatment contest in which agents who exert equal effort have an equal probability of success. In contrast, under affirmative action, agents with equal cost of effort have equal probability of success. We analyze such contests as generalized aggregative potential games and characterize their Nash equilibria. We show that affirmative action equalizes equilibrium payoffs without causing any loss of aggregate welfare. It enhances the welfare and effort levels of agents facing high effort cost. Thus, affirmative action engenders equality without having any detrimental effects on efficiency, at least when the number of agents involved are large. It does, however, reduce aggregate effort in society.

Author Bio: Ratul Lahkar is Professor of Economics in Ashoka University . He received his masters in economics from the Delhi School of Economics and his PhD in economics from the University of Wisonsin-Madison in 2007. His primary research interest is in game theory with particular focus on evolutionary game theory. He has worked on both theoretical aspects of evolutionary games as well as applications in economics.

 

Lecture 22

Speaker: S. Nageeb Ali, Professor of Economics, Pennsylvania State University

Venue:  https://us02web.zoom.us/j/82080834043?pwd=Wkh5Z2JLS1JBVWNQUUFRZXhCVW56QT09

Date: 30th March 2021 | Add to Google Calendar

Time: 7.30PM India Time

Duration: 1 hour

Title: Reselling Information

Abstract: Information is replicable in that it can be simultaneously consumed and sold to others. We study how resale affects a decentralized market for information. We show that even if the initial seller is an informational monopolist, she captures non-trivial rents from at most a single buyer: her payoffs converge to 0 as soon as a single buyer has bought information. By contrast, if the seller can also sell valueless tokens, there exists a “prepay equilibrium” where payment is extracted from all buyers before the information good is released. By exploiting resale possibilities, this prepay equilibrium gives the seller as high a payoff as she would achieve if resale were prohibited.

Author Bio: Nageeb Ali is a Professor of Economics at Penn State University, where he has been teaching Economics since 2015. Prior to that, he was an Assistant Professor of Economics at UC San Diego, a Visiting Professor at Harvard University, and received his PhD in Economics from Stanford University in 2007. His work has been featured in publications such as Journal of Economic Theory, American Economic Review, and Quarterly Journal of Economics.

 

Lecture 21

Speaker: Asuman Ozdaglar, Massachusetts Institute of Technology

Venue:  https://us02web.zoom.us/j/85943104336?pwd=cE9YdFAyRnhaUXc0akZ1aGFtSWsydz09

Date: 16th March 2021 | Add to Google Calendar

Time: 7.30PM India Time

Duration: 1 hour

Title: Analysis and Interventions in Large Network Games

Abstract: 

In many social and economic settings, decisions of individuals are affected by the actions of their friends, colleagues, and peers. Examples include adoption of new products and innovations, opinion formation and social learning, public good provision, financial exchanges and international trade. Network games have emerged as a powerful framework to study these settings with particular focus on how the underlying patterns of interactions, governed by a network, affect the economic outcomes. For tractability reasons, much of the work in this area studied games with special structure (e.g., quadratic cost functions, scalar non-negative strategies) or special properties (e.g., games of strategic complements or substitutes).

In this talk, we first present a unified framework based on a variational inequality reformulation of the Nash equilibrium to study equilibrium properties of network games including existence and uniqueness, convergence of the best response dynamics and comparative statics. Our framework extends the literature in multiple dimensions, covering games with general strategic interactions and multidimensional and constrained strategy sets. In the second part of the talk, we will present a new class of infinite populations games, graphon games, that can capture heterogenous local interactions. We will show that equilibria in graphon games can approximate the equilibria of large network games sampled from the graphon. We also show that (under some regularity assumptions on the graphon), interventions based on graphon games can be designed using computationally tractable optimization problems and with much less information than the entire network structure.

Author Bio: Asu Ozdaglar received the B.S. degree in electrical engineering from the Middle East Technical University, Ankara, Turkey, in 1996, and the S.M. and the Ph.D. degrees in electrical engineering and computer science from the Massachusetts Institute of Technology, Cambridge, in 1998 and 2003, respectively.
She is the MathWorks Professor of Electrical Engineering and Computer Science in the Electrical Engineering and Computer Science (EECS) Department at the Massachusetts Institute of Technology. She is the department head of EECS and she Deputy Dean of Academics in the Schwarzman College of Computing. Her research expertise includes optimization theory, with
emphasis on nonlinear programming and convex analysis, game theory, with applications in communication, social, and economic networks, distributed optimization and control, and network analysis with special emphasis on contagious processes, systemic risk and dynamic control.
Professor Ozdaglar is the recipient of a Microsoft fellowship, the MIT Graduate Student Council Teaching award, the NSF Career award, the 2008 Donald P. Eckman award of the American Automatic Control Council, the Class of 1943 Career Development Chair, the inaugural Steven and Renee Innovation Fellowship, and the 2014 Spira teaching award. She served on the Board of Governors of the Control System Society in 2010 and was an associate editor for IEEE Transactions on Automatic Control. She was the inaugural area co-editor for the area entitled "Games, Information and Networks” in the journal Operations Research. She is the co-author of
the book entitled “Convex Analysis and Optimization” (Athena Scientific, 2003).

 

Lecture 20

Speaker: Yotam Gafni & Elisheva Shamash, PhD Candidate, Technion - Israel Institute of Technology

Venue: https://us02web.zoom.us/j/86954996498?pwd=YXhzL3dtTTE5ZnNzMkZEWFcrVHJqUT09

Date: 2nd March 2021 | Add to Google Calendar

Time: 7.30PM India Time

Duration: 1 hour

Title 1: VCG Under Sybil (False-name) Attacks—a Bayesian Analysis

Author: Yotam Gafni, Ron Lavi, & Moshe Tenneholtz

Abstract: VCG is a classical combinatorial auction that maximizes social welfare. However, while the standard single-item Vickrey auction is false-name-proof, a major failure of multi-item VCG is its vulnerability to false-name attacks. This occurs already in the natural bare minimum model in which there are two identical items and bidders are single-minded. Previous solutions to this challenge focused on developing alternative mechanisms that compromise social welfare. We re-visit the VCG auction vulnerability and consider the bidder behavior in Bayesian settings. In service of that we introduce a novel notion, termed the granularity threshold, that characterizes VCG Bayesian resilience to false-name attacks as a function of the bidder type distribution. Using this notion we show a large class of cases in which VCG indeed obtains Bayesian resilience for the two-item single-minded setting.

Author Bio: Yotam Gafni is a PhD candidate at Technion - Israel Institute of Technology

 

Title 2: Principal-Agent VCG Contracts

Author: Ron Lavi & Elisheva Shamash

Abstract:  We study a complete information game with multiple principals and multiple common agents. Each agent takes an action that can affect the payoffs of all principals. Prat and Rustichini (Econometrica, 2003) who introduce this model assume first price contracts: each principal offers monetary transfers to each agent conditional on the action taken by the agent. We define VCG contracts in which the monetary transfers to each agent additionally depend on all principals' offers, and study its effect on the existence of efficient pure subgame perfect equilibrium outcomes. We characterize a necessary and sufficient condition for the existence of a pure subgame perfect equilibrium (SPE) with VCG contracts. As a consequence, we show that the class of instances that admit an efficient SPE with VCG contracts strictly contains the class of instances that admit an efficient SPE with first price contracts, and in fact the difference between these two sets has positive measure. Although VCG contracts broaden the existence of pure subgame perfect equilibria, we show that the worst case welfare loss in a SPE outcome, over all games with any fixed M>3 number of principals, is the same for both VCG contracts and first price contracts.

Author Bio: Elisheva Shamash is a PhD candidate at Technion - Israel Institute of Technology

 

 

Lecture 19

Speaker: Yang Sun, Assistant Professor of Economics, Sichuan University, China

Venue: https://us02web.zoom.us/j/81008585314?pwd=c2dDWkpEK1dPRnFsaFdkV1RFN2tFQT09

Date: 17th February 2021 | Add to Google Calendar

Time: 7.30PM India Time

Duration: 1 hour

Title: Structural Interventions in Networks

Author: Yang Sun, Wei Zhao, & Junjie Zhou

Abstract: Two types of interventions are commonly implemented in networks: characteristic intervention which influences individuals’ intrinsic incentives, and structural intervention which targets at the social links among individuals. In this paper we provide a general framework to evaluate the distinct equilibrium effects of both types of interventions. We identify a hidden equivalence between a structural intervention and an endogenously determined characteristic intervention. Compared with existing approaches in the literature, the perspective from such an equivalence provides several advantages in the analysis of interventions targeting on network structure. We present a wide range of applications of our theory, including identifying the most wanted crim-
inal(s) in delinquent networks and targeting the key connector for isolated communities.

Author Bio: Dr. Yang Sun is an Assistant Professor of Economics at Sichuan University, China. His research interests are Microeconomics, Game Theory, and Networks.

 

Lecture 18

Speaker: Hector Tzavellas, PhD candidate in Economics at George Washington University

Venue: https://us02web.zoom.us/j/88488552169?pwd=UVBHd3ZZRTdwMEhNRzVSNmV5Rno3QT09

Date: 2nd February 2021 | Add to Google Calendar

Time: 9AM EST7.30PM India Time

Duration: 1 hour

Title: Systemic Importance and Aggregate Fluctuations with Multiplex Interactions

Author: Hector Tzavellas

Abstract: A substantial literature has studied the propagation and amplification of microeconomic shocks within a monolayer network. However, transmission of shocks through interrelated multilayer networks is not yet understood. We propose a reduced form model of multidimensional economic interdependence, featuring complementary or substitutionary actions of agents active in multiple networks. The model extends the monolayer network concepts of systemic importance and micro-induced aggregate fluctuations to their multi-layered counterparts, where an idiosyncratic shock can cascade through both intra- and inter-network margins. We find that the centrality rankings of agents in a single network are no longer sufficient to identify key agents in a multilayer framework. Agents least central in one network may be systemically more important in the aggregate system due to their capacity to produce cascades across networks. A narrow focus on a single network may lead to an overestimation of individual systemic importance. We also show that microeconomic shocks can generate higher aggregate volatility in a multilayer network, especially when complementarity among networks with similar interconnection patterns transmit and amplify idiosyncratic disturbances. As a consequence, economies exhibiting multiplex connectivity are more prone to large downturns.

Author Bio: Hector is a Ph.D. candidate at The George Washington University in Washington, D.C. His current research lies in the intersection of Macroeconomic Theory and the Economics of Networks. It focuses on the theoretical foundations of multidimensional economic connectivity as they relate to issues of systemic importance, micro-induced macroeconomic fluctuations and network formation.

 

Lecture 17

Speaker: Yusufcan Masatlioglu, Professor of Economics at the University of Maryland.

Venue: https://us02web.zoom.us/j/82063472071?pwd=M3ZPMXBXNHlqeCtxeTkwbXo3Snhudz09

Date: 19th January 2021 | Add to Google Calendar

Time: 9AM EST7.30PM India Time

Duration: 1 hour

Title: Progressive Random Choice

Authors: Emel Filiz-Ozbay, Yusufcan Masatlioglu

Abstract: We introduce a new model of stochastic choice, the "Progressive Random Choice (PRC) model.'' In a PRC model, the decision-maker randomizes over a collection of choice functions which are ordered with respect to some reference order and we call this structure progressiveness. A PRC representation identifies the collection of choices and associated probabilities uniquely, moreover, it can explain a rich set of stochastic choice. We are particularly interested in PRC where each choice function satisfies a well-known bounded rationality structure, namely "less-is-more.'' The characterization of less-is-more-PRC relies on two simple axioms: U-regularity and weak-regularity. We further show that the reference ordering can be endogenously derived in this class.

Author Bio: Yusufcan Masatlioglu is a professor of Economics at the University of Maryland. Prof. Masatlioglu has developed a deep and important research agenda in the area of bounded rationality and decision theory. He joined the economics department of the University of Michigan in the Fall of 2005 after obtaining a Ph.D. in Economics at New York University. Prof. Masatlioglu did his Bachelor's degree from the Bogazici University of Istanbul, and his Master’s and Ph.D. in Economics from NYU. He also worked at the University of Michigan between 2005-2016.

Prof. Masatlioglu is best known professionally for his work on developing theoretical foundations for Reference Dependent Choice, Time Preferences, Limited Attention, Bounded Rationality, and Willpower. He has published his work regularly in leading academic journals, such as the American Economic Review, Review of Economic Studies, Journal of Political Economy. His work on limited attention is rewarded by two prestigious National Science Foundation grants. His work is at the forefront of his field. He has been regarded as one of the top decision theorists worldwide and received many invitations as a seminar speaker and conference participant, such as Harvard, MIT, Berkeley, NYU, Oxford, etc. He is currently a co-editor at the Mathematical Social Sciences.

 

Lecture 16 (Watch the video)

Speaker: Mark Broom, Professor in Mathematics, City University of London

Venue: https://us02web.zoom.us/j/87854540060?pwd=OHpST2J3UUxHNytKQko2NFlGaEoxUT09

Date: 26th November 2020

Time: 2PM London Time, 7.30PM India Time

Duration: 1 hour

Title: Modelling evolution in structured populations involving multiplayer games

Abstract: Since 2005 models of evolution have incorporated structured populations, including spatial structure, through the modelling of evolutionary processes on graphs (evolutionary graph theory). One limitation of this otherwise quite general framework is that interactions are restricted to pairwise ones, through the edges connecting pairs of individuals. Yet many animal interactions can involve many individuals, and theoretical models also describe such multi-player interactions. We shall discuss a more general modelling framework of interactions of structured populations where multi-player contests involving groups of variable size are included. We can embed the results of different evolutionary games within our structure, as occurs for pairwise games such as the Prisoner's Dilemma or the Hawk-Dove game on graphs. We will also discuss multiplayer games more generally in the context of the evolution of cooperative behaviour.

Author Bio: Professor Mark Broom obtained a BA (Hons) in Mathematics from the University of Oxford in 1989, followed by an MSc in Statistics (1990) and a PhD in Mathematics (1993) at the University of Sheffield. He then held a postdoctoral research position again at Sheffield (1993-5) and a temporary lecturing position at the University of Glasgow (1995-6). He joined the University of Sussex as a Lecturer in 1996, where he worked until the end of 2009, most recently as Reader in Mathematics, and he was the Head of the Department of Mathematics from 2007 to 2009. Mark was appointed as Professor of Mathematics at City University in January 2010. He became Head of the Department of Mathematics in August 2021. In 2013, together with Jan Rychtář, he completed the book Game-Theoretical Models in Biology published by Chapman and Hall. A second edition is in preparation, due to appear towards the end of 2021. 
He is on the Editorial Board of the Journal of Theoretical Biology, Dynamic Games and Applications and of the newly created Chapman and Hall Mathematical Biology book series.

 

Lecture 15 (Watch the video)

Speaker: Matthew Jackson, Professor of Economics at Stanford University.

Venue: https://us02web.zoom.us/j/87384791822?pwd=WU5jbUpPcjJjMHE3ZUZMQXJhOTFtUT09

Date: 10th November 2020

Time: 7AM PST, 8.30PM India Time

Duration: 1 hour

Title: The Role of Referrals in Inequality, Immobility, and Inefficiency in Labor Markets

Authors: Lucas Bolte, Nicole Immorlica, Matthew Jackson

Abstract: We study the consequences of job markets' heavy reliance on referrals.    Referrals screen candidates and lead to better matches and increased productivity, but disadvantage job-seekers who have few or no connections to employed workers, leading to increased inequality.  Coupled with homophily, referrals also lead to immobility:  a demographic group's low employment rate in one period leads that group to have relatively low employment in future periods as well.  We identify conditions under which distributing referrals more evenly across a population not only reduces inequality, but also improves economic mobility across generations as well as future productivity.  We use the model to examine optimal policies, showing that one-time affirmative action policies involve short-run production losses, but lead to long-term improvements in equality, mobility, and productivity due to induced changes in future referrals.  We examine how the possibility of firing workers changes the effects of referrals.

Author Bio: Matthew O. Jackson is the William D. Eberle Professor of Economics at Stanford University and an external faculty member of the Santa Fe Institute. He was at Northwestern University and Caltech before joining Stanford, and received his BA from Princeton University in 1984 and PhD from Stanford in 1988. Jackson's research interests include game theory, microeconomic theory, and the study of social and economic networks, on which he has published many articles and the books `The Human Network' and `Social and Economic Networks'. He also teaches an online course on networks and co-teaches two others on game theory. Jackson is a Member of the National Academy of Sciences, a Fellow of the American Academy of Arts and Sciences, a Fellow of the Econometric Society, a Game Theory Society Fellow, and an Economic Theory Fellow, and his other honors include a Guggenheim Fellowship, the Social Choice and Welfare Prize, the von Neumann Award from Rajk Laszlo College, an honorary doctorate from Aix-Marseille University, the B.E.Press Arrow Prize for Senior Economists, and teaching awards. He has served on the editorial boards of Econometrica, Games and Economic Behavior, PNAS, the Review of Economic Design, and as the President of the Game Theory Society.

 

Lecture 14 (Watch the video)

Speaker: Prof Bhaskar Dutta, Professor of Economics at Ashoka University and University of Warwick.

Venue: https://us02web.zoom.us/j/88278371520?pwd=WUplNzR2YUI1K3Q1clVtWjlLLzdXQT09

Date: 13th October 2020

Time: 6.30PM India Time

Duration: 1 hour

Title: Defence and Interception in Networks

Authors: Francis Bloch, Kalyan Chatterjee, Bhaskar Dutta

Abstract:  An Attacker (A) and a set of target nodes are connected in an exogenously given directed network. Each target node i has a value b_i. Each node has to decide on level or probability of detection, probability x costing x^2/2 . A can "attack" any node i, choosing a path through the network with terminal node i. The attack succeeds if A can evade detection at all nodes in the chosen path. A successful attack on node i gives A benefit b_i, while i loses b_i as well as cost of detection. We focus on the noncooperative game where A chooses a path and each node i chooses level x_i. We show that there is a unique equilibrium and characterize the equilibrium. We then compare the noncooperative equilibrium with the cooperative equilibrium where network defence is coordinated by a central planner.

Author Bio: Bhaskar Dutta is Professor of Economics at Ashoka University and University of Warwick. His research interests include Cooperative Game Theory, Mechanism Design, Formation of Groups and Networks, Social Choice Theory and Development Economics.

He has had a long association with the Indian Statistical Institute, where he has taught during 1979 -2002. He has also been a Visiting Professor in several universities. He was awarded the Mahalanobis Memorial Award of the Indian Econometric Society in 1990. He was President of the Society for Social Choice and Welfare (2014-16). He is also a Fellow of the Econometric Society, Game Theory Society and the Society for Advancement of Economic Theory. He has been Chair, Standing Committee for India and South Asia as well as a member of the Council of the Econometric Society. He has also been a member of the Council of the Game Theory Society. He has also served
as consultant for the World Bank, UNDP, ILO and ADB.

Prof. Dutta has published extensively in leading journals, applying game-theoretic tools in the areas of mechanism design, cooperative game theory, the economic theory of social networks, and social choice theory. He was a Managing Editor of Social Choice and Welfare, and is currently Advisory Editor of  Games and Economic Behaviour. He has also edited several books. Prof. Dutta did his Bachelor's degree from the University of Calcutta, and his Master’s and Ph.D. in Economics from the University of Delhi.

 

Lecture 13 (Watch the video)

Speaker: Prof Georges ZaccourChair in Game Theory and Management, HEC Montréal, Canada

Venue: https://us02web.zoom.us/j/83664298449?pwd=MmJyS3NCR0FXY09TemJrWkpJT0Q0Zz09

Date: 30th September 2020

Time: 6.30PM India Time

Duration: 1 hour

Title: Sustainability of Cooperation in Dynamic Games Played over Event Trees

Abstract:  Many problems in economics, engineering and management science have the following three features in common: (a) They involve only a few agents (players) who have interdependent payoffs. (b) The agents cooperate or compete repeatedly over time, and the problem involves an accumulation process, e.g., production capacity, pollution stock. (c) Some of the parameter values are uncertain. A natural framework to deal with such problems is the theory of dynamic games played over event trees (DGPETs). If the players decide to coordinate their strategies by signing a long-term contract, then they must ensure that all players follow their cooperative commitments as time goes by. In this talk, I discuss different approaches to sustain cooperation over time in DGPETs.

Author Bio: Georges Zaccour holds the Chair in Game Theory and Management and is full professor of Management Science at HEC Montréal. He holds a Ph.D. in management science, an M.Sc. in international business from HEC Montréal and a licence in mathematics and economics from Université Paris-Dauphine. He served as director of GERAD, marketing department and Ph.D. program at HEC Montréal. His research areas are differential games, optimal control and operations, areas in which he has published more than one hundred papers and co-edited thirteen volumes. He coauthors the books Differential Games in Marketing and Games and Dynamic Games (to appear). His research is regularly funded by the Natural Sciences and Engineering Research Council of Canada. He is editor-in-chief of Dynamic Games and Applications and associate editor for several journals. He is fellow of The Royal Society of Canada and was president of the International Society of Dynamic Games (2002-2006).

 

Lecture 12 (Watch the Video)

Speaker: Prof Rahul Roy, Professor at Indian Statistical Institute, New Delhi. 

Venue: https://us02web.zoom.us/j/86322143843?pwd=M3p2QWNTNDNzL0loRWE5Kzlkc0VxQT09

Date: 15th September 2020

Time: 6.30PM India Time

Duration: 1 hour

Title:  Voter and Majority Dynamics with Biased and Stubborn Agents

Authors: Arpan Mukhopadhyay, Ravi R. Mazumdar, & Rahul Roy

Abstract:  

We study binary opinion dynamics in a fully connected network of interacting agents. The agents are assumed to interact according to one of the following rules:

(1) Voter rule: An updating agent simply copies the opinion of another randomly sampled agent;

(2) Majority rule: An updating agent samples multiple agents and adopts the majority opinion in the selected group.

We focus on the scenario where the agents are biased towards one of the opinions called the preferred opinion. Using suitably constructed branching processes, we show that under both rules the mean time to reach consensus is theta(logN),where N is the number of agents in the network. Furthermore, under the majority rule model, we show that consensus can be achieved on the preferred opinion with high probability even if it is initially the opinion of the minority. We also study the majority rule model when stubborn agents with fixed opinions are present. We find that the stationary distribution of opinions in the network in the large system limit using mean field techniques

Author Bio: Rahul Roy is a professor at the Indian Statistical Institute, New Delhi. He works in probability theory and, more particularly, in percolation theory and random graphs. He is also interested in the history of mathematics. He is a fellow of the Indian Academy of Sciences, and he obtained his Ph.D. from Cornell University. His book with Ronald Meester 'Continuum Percolation' is considered a classic in the domain.

Lecture 11 (Watch the Video)

Speaker: Prof Tamer Başar, Director, Center for Advanced Study, University of Illinois at Urbana-Champaign .

Venue: https://us02web.zoom.us/j/86436781995?pwd=a21qSGZPQW5YNWR6RjFGOHZLSVJiZz09

Date: 1st September 2020

Time: 9AM CDT (7.30PM India Time)

Duration: 1 hour

Title:  Mean Field Differential Games with Elements of Robustness

Abstract:  Mean field games (MFGs) constitute a class of non-cooperative stochastic differential games (SDGs) with a large number of players who interact with each other through a mean field coupling term, appearing in the individual cost functions and/or each player’s dynamics described by a controlled stochastic differential equation. One of the main research issues in MFGs is to study the existence, uniqueness and characterization of Nash equilibria with an infinite population of players under specified information structures and further to study finite-population approximations, that is to what extent an infinite-population Nash equilibrium (NE) provides an approximate NE for the finite-population game.
Following a general overview of the difficulties brought about by strategic interactions in finite-population SDGs, the talk will dwell on two classes of MFGs: those characterized by risk sensitive (RS) objective functions and those that have risk-neutral (RN) objective functions but with an additional adversarial driving term in the dynamics (known as robust MFGs). The talk will discuss the connection between these two classes of MFGs, particularly with linear-quadratic structures, which will allow for closed-form solutions and explicit comparisons between the two in both infinite- and finite-population regimes and with respect to the approximation of NE in going from the former to the latter. The talk will conclude with a brief discussion of several extensions of the framework.

Author Bio: Tamer Başar received the B.S.E.E. degree from Robert College, Istanbul, and M.S., M.Phil., and Ph.D. degrees from Yale University. He is with the University of Illinois at Urbana-Champaign, where he holds the academic positions of Swanlund Endowed Chair; Center for Advanced Study Professor of Electrical and Computer Engineering; Research Professor at the Coordinated Science Laboratory; and Research Professor at the Information Trust Institute. He was the Editor-in-Chief of Automatica between 2004 and 2014, and is currently editor of several book series. He is also the Director of the Center for Advanced Study. He is a member of the US National Academy of Engineering and the European Academy of Sciences; Fellow of IFAC, and SIAM; a past president of the IEEE Control Systems Society (CSS), the founding president of the International Society of Dynamic Games (ISDG), and a past president of the American Automatic Control Council (AACC). His current research interests include stochastic teams, games, and networks; multi-agent systems and learning; data-driven distributed optimization; spread of information and epidemics; security and trust; energy systems; and cyber-physical systems. He has received several awards and recognitions over the years, including the highest awards of IEEE CSS, IFAC, AACC, and ISDG, the IEEE Control Systems Award, and a number of International Honorary Doctorates and Professorships. He has over 900 publications in systems, control, communications, networks, optimization, and dynamic games, including books on non-cooperative dynamic game theory, robust control, network security, wireless and communication networks, and stochastic networked control.

 

Lecture 10 (Watch the video here)

Speaker: Prof Sudipta Sarangi, Department Head & Professor of Economics, Virginia Tech

Venue: https://us02web.zoom.us/j/84291065599?pwd=elB1VTloanpocDNScEVIbzdGWEl0Zz09

Date: 20th August 2020

Time: 9AM Eastern Time (6.30PM India Time)

Duration: 1 hour

Title:  Two Models of Multigraphs

Abstract:  Economic agents are typically connected to others in multiple network relationships, and the architecture of one network could be shaped by connections in other networks. In this talk we explore two models of network formation with multiple networks. In the first model, we assume that one network is given and examine how its structure affects the formation of the other network. In the second model we use a degrees-based approach to study the formation of two networks simultaneously under different conditions.

Author Bio: Sudipta Sarangi is one of the founding members of GamesNet. His research interests lie in economic theory and its application to areas like networks, development economics and experimental economics. In 2020, he received the Kuznets Prize for his research on the historical origins of Gender Inequality. He serves on the editorial boards of Journal of Economic Behavior and OrganizationJournal of Public Economic TheoryEconomic Modelling and Studies in Microeconomics. He is a Research Associate of DIW Berlin, GATE, University of Lyon-St. Etienne and the Lima School of Economics. Previously he has worked at the National Science Foundation and was a Distinguished Professor of Business Administration at Louisiana State University. He is currently Department Head and Professor of Economics at Virginia Tech. His book The Economics of Small Things will be published by Penguin India in November 2020. 

 

Lecture 9 (Watch the video here)

Speaker: Prof. Sanjeev Goyal, Professor of Economics and a Fellow of Christ's  College, Cambridge

Venue: https://us02web.zoom.us/j/83969041714?pwd=a21jcG0rbWZvNklxK3pZUWNjQVVWZz09

Date: 4th August 2020

Time: 2PM BST (6.30PM India Time)

Duration: 1 Hour

Title:  Large Scale Experiments on Networks: A New Platform with Applications

Authors: Choi, S., Goyal, G. and Moisan, F.

Abstract:  This paper presents a new platform for large scale networks experiments in continuous time. The versatility of the platform is illustrated through three experiments: a game of linking, a linking game with public goods, and a linking game with trading and intermediation. Group size ranges from 8 to 100 subjects. These experiments reveal that subjects create sparse networks that are almost always highly efficient. In some experiments the networks are centralized and unequal, while in others they are dispersed and equal. These network structures are in line with theoretical predictions, suggesting that continuous time asynchronous choice facilitates a good match between experimental outcomes and theory. The size of the group has powerful effects on individual investments in linking and effort, on network structure, and on the nature of payoff inequality. Researchers should therefore exercise caution in drawing inferences about behaviour in large scale networks based on data from small group experiments.

Author Bio: Sanjeev Goyal is Professor of Economics and a Fellow of Christ's  College, Cambridge. He got his BA from the University of Delhi, his MBA  from IIM Ahmedabad, and his Ph.D from Cornell University. He has  previously held Chairs at Erasmus University Rotterdam, University of  London, and Essex University, and was Wesley Clair Mitchell Visiting  Professor at Columbia University in Spring, 2020.

He is a pioneer and leading international scholar in the study of networks. His book, `Connections: an introduction to the economics of networks`, was published in 2007 by Princeton University Press. A  Chinese translation appeared in 2010.

He is a Fellow of the British Academy, a Fellow of the Econometric Society, and a member of the Council of the Game Theory Society. He was the Founding Director of the Cambridge-INET Institute  (2012-2014) and  Chair of the Economics Faculty at Cambridge, 2014-2018.

 

Lecture 8 

Speaker: Prof.  Adam Dominiak, Associate Professor of Economics at Virginia Tech

Venue: https://us02web.zoom.us/j/87253696452?pwd=MUV0dmxrU0ZMaUxXbC9OOXhXYnpNdz09

Date: 21st July 2020

Time: 10AM EST (7.30PM India Time)

Duration: 1.5 Hour (Note the longer duration)

Title:  Decision Making Under Ambiguity

Authors: Adam Dominiak

Abstract:  Ambiguity refers to choice situations under uncertainty with unknown probabilities of states.  Ambiguity is ubiquitous in the real world. Daniel Ellsberg introduced ambiguity into economics in his seminal 1961 article. In a series of elegant thought-experiments, he conjectured that individuals might be ambiguity averse; i.e., they might prefer betting on states with known probabilities rather than betting on states with unknown probabilities. Ambiguity aversion violates the classical models of choice that rely on the hypothesis that individuals’ beliefs can be represented by a unique probability distribution. Nowadays ambiguity aversion is a well-documented behavior. Many formal models have been developed in order to accommodate the phenomena of ambiguity and ambiguity aversion into economic theory. This survey provides a brief review of the popular ambiguity models. Starting with the classical Subjective Expected Utility (SEU) theory of Leonard Savage and the Ellsberg paradox, it presents three extensions of SEU with different representations of ambiguity and ambiguity aversion. It continues with an economic application.  Finally, it discusses some extensions of ambiguity models to dynamic choice problems.

Author Bio: Adam Dominiak is currently an Associate Professor of Economics at Virginia Tech with research interests in areas of Decision Theory, Game Theory, Experimental Economics, Behavioral Economics, and Epistemic Game Theory. 

He obtained his PhD from the University of Heidelberg and has been a visiting professor at UC Davis, Kellogg School of Management and Paris-Dauphine University. He has published in the top theory journals like Games and Economic Behavior, Economic Theory, Management Science and Journal of Mathematical Economics. He is currently the Guest Editor of a Special Issue of Theory and Decision in honor of Jurgen Eichberger.

 

Lecture 7 (Watch the video here)

Speaker: Prof. Michel Grabisch, Professor of Computer Sciences at Université Paris I Panthéon-Sorbonne and Associated Professor at Paris School of Economics

Venue: https://virginiatech.zoom.us/j/3560436013

Date: 7th July 2020

Time: 3PM CEST (6.30PM India Time)

Duration: 1 Hour

Title: Opinion dynamics: a survey

Authors: Michel Grabisch

Abstract: With the development of network theory, there is a huge literature on how opinion in a society of agents is evolving, due to interactions between agents. While sociologists have initiated many fundamental models, other disciplines have significantly contributed to the field: economists have incorporated strategic considerations, physicists have considered agents as particles and created sociophysics, computer scientists treated agents as automata, and control theorists have considered the dynamics of opinion as a particular input/output system. This short survey focuses on nonstrategic models, considering either that opinion is a binary (yes/no), or is continuous. Starting from classical models (essentially the threshold model for binary opinion, and the DeGroot model for continuous opinion), it shows the main variants of them, putting emphasis on two aspects which are of recent interest: anti-conformity behavior, and time-varying models.

Author Bio: Michel Grabisch started his career as research engineer at Thomson-CSF, and is since 2002 full professor of computer sciences at Université Paris I Panthéon-Sorbonne and associated professor at Paris School of Economics. He is the head of the Theoretical MicroEconomics group at Centre d'Economie de la Sorbonne and honorary senior member of the Institut Universitaire de France.
His research interests are game theory, decision theory, networks and opinion formation, and discrete mathematics. He has authored and co-authored more than 120 papers in refereed international journals, 5 books, and more than 100 papers in refereed international conferences. He is co-editor-in-chief of 4OR, and associate editor of Annals of Operations Research, Mathematical Social Sciences, Order and several other journals.

 

Lecture 6 (Watch the video here, Download presentation)

Speaker: Prof. Herve Moulin, Donald J. Robertson Chair of Economics at the Adam Smith Business School at the University of Glasgow

Venue: https://us02web.zoom.us/j/88481109223?pwd=ZDlPd3BUa3dVUXpVR3lBSWxIbkdBdz09

Meeting ID: 884 8110 9223
Password: 277589

Date: 23rd June 2020

Time: 2PM BST (GMT +1, 6.30PM India Time)

Duration: 1 Hour

Title: Fair Division with Money

Authors: Anna Bogomolnaia and Herve Moulin

Abstract: 

Agents share indivisible objects (desirable or not) and use cash transfers to achieve fairness. Utilities are linear in money but otherwise arbitrary. We look for n-person division rules preserving the informational simplicity of Divide and Choose or the Texas Shoot Out between two agents, treating agents symmetrically, and offering high individual welfare Guarantees.

A single bidding for the whole manna is one such method but it does not capture the potential efficiency gains from debundling the objects as in Divide and Choose. Our Bid and Choose rules fix a benchmark price p for the objects; in each of the n-1 rounds of bidding the winner must pay for the remaining objects he picks. These rules are much simpler than Kuhn's n-person generalisation of Divide and Choose, and they typically offer better Guarantees. They help agents with subadditive utilities, to the detriment of those with superadditive utilities.

Author Bio: Hervé Moulin is the Donald J. Robertson Chair of Economics at the Adam Smith Business School at the University of Glasgow. He is known for his research contributions in mathematical economics, in particular in the fields of mechanism design, social choice, game theory and fair division. He has written six books and over 100 peer-reviewed articles. Before joining the University of Glasgow, he was the George A. Peterkin Professor of Economics at Rice University (from 1999 to 2013), the James B. Duke Professor of Economics at Duke University (from 1989 to 1999) and the University Distinguished Professor at Virginia Tech (from 1987 to 1989).
He is a fellow of the Econometric Society since 1983, and the President of the Game Theory Society since 2018. He also served as president of the Society for Social Choice and Welfare for the period of 1998 to 1999. He is a fellow of the Royal Society of Edinburgh. He is also a Fellow of the British Academy.
Moulin obtained his doctoral degree in Mathematics at the University of Paris in 1975 with a thesis on zero-sum games, which was published in the Journal of Mathematical Analysis and its Applications. On 1979, he published a seminal paper in Econometrica introducing the notion of dominance solvable games. His work on this concept was mentioned in Eric Maskin's Nobel Prize Lecture. Moulin is credited as the first proposer of the famous beauty contest game. Experiments testing the equilibrium prediction of this game started the field of experimental economics.

 

Lecture 5 (Watch the video here)

Speaker: Prof. Juan D Moreno-TerneroProfessor at the Department of Economics, University Pablo de Olavide (Seville)

Venue: https://us02web.zoom.us/j/83821255038?pwd=ZldZU2N6UHJCUi83eXJ5VVI5VHA2Zz09
 

Meeting ID: 838 2125 5038
Password: 277589

Date: 11th June 2020

Time: 3PM CEST (GMT +2, 6.30PM India Time)

Duration: 1 Hour

Title: Fair international protocols for the abatement of Greenhouse Gas (GHG) emissions

Authors: Biung-Ghi Ju, Min Kim, Suyi Kim, Juan D. Moreno-Ternero

Abstract: We study the design of fair international protocols for the abatement of GHG emissions. We formulate normative principles, pertaining to countries’ population, emission history, and (business as usual) future emissions, as axioms for allocation rules. We show that combinations of these axioms characterize the so-called equal per capita allocation rules, with or without historical accountability. The allocations these rules generate are in stark contrast with the allocation suggested by the Kyoto protocol, which is close to the allocation in proportion to the current and business-as-usual emissions, suggested by the proportional (grandfathering) rule. As we illustrate, equal per capita allocations admit more emissions to developing countries with large populations. And, with historical accountability, developed countries with large historical emissions are clearly penalized.

Author Bio: Juan D. Moreno-Ternero is a Professor at the Department of Economics, University Pablo de Olavide (Seville) and an Affiliate Research Fellow at the Seoul National University Center for Distributive Justice. He holds a Ph.D. in Economics from the University of Alicante and was a Postdoctoral Fellow at the Department of Political Science, Yale University, and at CORE, Université catholique de Louvain. His research interests include distributive justice, welfare economics, health economics, and political economy. He has published some 40 articles on these topics in journals such as Econometrica, Management Science, International Economic Review, Games and Economic Behavior, or Journal of Health Economics. He currently serves as co-Editor of the journals Mathematical Social Sciences, and SERIEs (Journal of the Spanish Economic Association), as well as Associate Editor of Economic Theory and Economic Theory Bulletin.

Lecture 4

Speaker: Prof. Kaushik Basu, Professor of Economics and the Carl Marks Professor of International Studies at Cornell University

Venue: https://zoom.us/j/93333479912?pwd=SzJ6WDRZTG9BOEVMYzRVN1ZFTk5yUT09

Meeting ID: 933 3347 9912
Password: 843233

Date: 2nd June 2020

Time: 9.30AM EDT (GMT - 4, 7PM India Time)

Duration: 1 Hour

Title: The Samaritan’s Curse: Moral Individuals and Immoral Groups

Abstract: The paper revisits the question of how and in what sense can individuals comprising a group be held responsible for morally reprehensible behavior by that group. The question is tackled by posing a counterfactual: what would happen if selfish individuals became moral creatures, instead? A new game, the Samaritan’s Curse, is introduced, which sheds light on the moral philosopher’s dilemma of group moral responsibility, but also opens up new questions concerning conferred morality and self-fulfilling morals, and implicit assumptions in game-theoretic arguments.

Author Bio: Kaushik Basu is Professor of Economics and the Carl Marks Professor of International Studies at Cornell University, and former Chief Economist of the World Bank (2012-16). From December 2009 to July 2012 he served as the Chief Economic Advisor to the Government of India. Earlier he was Professor of Economics at the Delhi School of Economics, where in 1992 he founded the Centre for Development Economics and was its first Executive Director. He is a Fellow of the Econometric Society and has received several honorary degrees, including doctorates from IIT Bombay, and Fordham University, New York. He is the author of several books, the most recent being The Republic of Beliefs: A New Approach to Law Economics (Princeton University Press, 2018). In May 2008, he was awarded one of India’s highest civilian awards, the Padma Bhushan, by the President of India.

 

 

Lecture 3 (Watch the video here)

 

Speaker: Prof. Kalyan Chatterjee, Distinguished Professor of Economics and Management Science at Penn State University

Venue: https://zoom.us/j/93924835672

Date: 19th May 2020

Time: 9AM Eastern Time (GMT - 5, 6.30PM India Time)

Duration: 1 Hour

Title: Competition and price formation 

Abstract: In this talk, I discuss some past work, including some of my own with co-authors, on modelling the fine structure of small markets. The focus is on understanding whether the pressure of competition drives prices of the same goods in different markets to be identical. Auctions and markets in which transactions are bilateral are two examples. Price dispersion is also discussed. The presentation is for general audiences, but is based on economic theory. It was given as one of the RC Dutt Memorial Lectures at the Centre for Studies in Social Sciences at Kolkata a few years ago.

Author Bio: Kalyan Chatterjee holds the title of Distinguished Professor of Economics and Management Science at Penn State University. He graduated in Physics from Presidency College, then studied at IIM Kolkata before getting a DBA from Harvard University. His research interests cover game theory and its applications in industrial organization and R&D models, decision theory, bargaining and negotiation-models and experiments, coalition formation and stability, incomplete contracts, complexity of strategies in games, economics of social networks. He has published in all the top journals and has served as the Chair for 42 doctoral students. Prof. Chatterjee is a Fellow of the Econometric Society, Member of the Institute for Advanced Study at Princeton University and has a long list of other honors.

 

Lecture 2 (Watch the video here)

 

Speaker: Prof. Benjamin Golub, Department of Economics, Harvard University

Venue: https://zoom.us/j/93924835672

Date: 5th May 2020

Time: 7AM Eastern Time (GMT - 5, 4.30PM India Time)

Duration: 1 Hour

Title: Supply Network Formation and Fragility (with Matt Elliott and Matt V. Leduc

Abstract: We model the production of complex goods in a large supply network. Firms source several essential inputs through relationships with other firms. Due to the risk of such supply relationships being idiosyncratically disrupted, firms multisource inputs and invest to make relationships with suppliers stronger. In equilibrium, aggregate production is robust to idiosyncratic disruptions. However, depending on parameters, the supply network may be robust or arbitrarily sensitive to small aggregate shocks that affect the functioning of relationships. We give conditions under which the equilibrium network is driven to a fragile configuration, where arbitrarily small aggregate shocks cause discontinuous losses. We use the model to provide a unified account of a number of stylized facts about complex economies.

Author Bio: Benjamin Golub’s research in economic theory focuses on social and economic networks. Since 2015, Ben has been on the faculty at the Harvard Department of Economics, where he is now Associate Professor; prior to that he spent two years as a Junior Fellow (2013-15) at the Harvard Society of Fellows. He has received the NSF CAREER grant (2019) and the Aliprantis Prize (2012) with Matt Elliott for an outstanding paper by a young economic theorist. He was educated at Stanford (Ph.D. in economics) and Caltech (B.S., mathematics).


Lecture 1

 

Speaker: Prof. Francis Bloch, Paris School of Economics

Venue: https://zoom.us/j/93924835672

Date: 21st April 2020

Time: 3PM Paris Time (GMT + 2, 6.30PM India Time)

Duration: 1 Hour

Title: A Game of Hide and Seek in Networks (with B Dutta and M Dziubinski) (Get the PRESENTATION | Get the PAPER)

Abstract: We propose and study a strategic model of hiding in a network, where the network designer chooses the links and his position in the network facing the seeker who inspects and disrupts the network. We characterize optimal networks for the hider, as well as equilibrium hiding and seeking strategies on these networks. We show that optimal networks are either equivalent to cycles or variants of a core-periphery networks where every node in the periphery is connected to a single node in the core.