Author: Imre Dimény

Martin Černý (Charles University, Department of Applied Mathematics) will present his paper on “Dealing with uncertainty in cooperative game theory” on December 18th at 11:00 AM, room QA406.

Abstract:   

Incomplete cooperative games generalise the classical model of cooperative games by omitting the values of some of the coalitions. This allows to incorporate uncertainty into the model and study the underlying games as well as possible payoff distribution based only on the partial information. In this paper we perform a systematic study of incomplete games, focusing on two important classes of cooperative games: positive and convex games. Regarding positivity, we generalise previous results for a special class of minimal incomplete games to general setting. We characterise non-extendability to a positive game by the existence of a certificate and provide a description of the set of positive extensions using its extreme games. The results are then used to obtain explicit formulas for several classes of incomplete games with special structures. The second part deals with convexity. We begin with considering the case of non-negative minimal incomplete games. Then we survey existing results in the related theory of set functions, namely providing context to the problem of completing partial functions. We provide a characterisation of extendability and a full description of the set of symmetric convex extensions. The set serves as an approximation of the set of convex extensions. Finally, we outline an entirely new perspective on a connection between incomplete cooperative games and cooperative interval games.

Krisztina Katona (University of Technology Sydney) will present his paper on “Essays in electricity market design and semi-structural price modelling” on December 4th at 11:00 AM, room QA406.

Abstract:   

Electricity market designs across the world are complex, diverse and constantly evolving frameworks of policies, with multidisciplinary theoretical work underpinning them. The fast transforming landscape of the electricity sector driven by cutting-edge optimization theory and the global commitment to meet emission goals calls for re-evaluating existing electricity market designs and price models. This thesis contributes to this discussion. To start, the first essay describes the general features of electricity markets. The second essay delves into an in-depth review of the market design of Australia’s National Electricity Market (NEM). This is followed by the third essay that presents a novel bid stack electricity price model that replaces the widely used exponential supply functions with hyperbolic ones to permit price negativity. Finally, focusing on the Pennsylvania-New Jersey-Maryland Interconnection (PJM) in the United States, the Balancing Market (BM) in Great Britain and the NEM in Australia, the fourth essay infers prices along the supply curves using largely the same optimization algorithms as the respective market operators do to assess the degree of supply monotonicity and compare welfare in these markets.

Marieke Pahlke  (Institute of Operations and Decision Sciences, Corvinus University) will present his paper on “Dynamic Consistency in Ambiguous Dutch Auctions” on November 27th at 11:00 AM, room QA406.

Abstract:   

We study a decreasing price auction with an ambiguity-neutral seller and two ambiguity-averse buyers. Due to the dynamic structure, buyers learn about the valuation of the opponent buyer during the auction. We characterize a belief formation process that allows buyers to consider their knowledge of the information structure. This process leads to a rectangular ex-ante belief set and implies dynamically consistent behavior. Then, we show that the seller can extract almost all surplus even if buyers behave dynamically consistently. Further, in our setting, buyers accept higher prices compared to a consistent planning approach.

Anastas Tenev  (Institute of Economics, Corvinus University) will present his paper on “Directed Reciprocity Subverts Altruism in Highly Adaptive Populations” on November 20th at 11:00 AM, room QA406.

Abstract:   

Directed reciprocity is generally considered to be a powerful driver for cooperation. Using extensive simulations within an established stylized framework, we test the strength of this relationship. We confirm that directed reciprocity boosts cooperation, but only in the case of relatively inert populations. For highly adaptive populations we find the opposite: directed reciprocity impedes cooperation. 

Luca Sandrini (Research Center of QSMS, BME) will present: “Protecting secrets with organizational innovations “ on March 14th at 2:30 PM, room QA 406.

Abstract:   

I propose a theory of the determinants of organizational innovation which considers it as a device to lower workers’ autonomy in the production process and their ability to collect information about it. In particular, I show that firms may have incentives to increase their control over the workforce to limit spillovers of potentially valuable information if they cannot limit workers’ mobility. I design a theoretical model where firms decide how to organize the workforce to reach a target level of productivity. I assume workers’ effort increases productivity at the organizational level, but it may reduce workers learning if excessive. When firms face the threat of information spillovers regarding their secrets, they are keener to intensify control over the workforce to limit it. From a policy perspective, I show banning laws restricting workers’ mobility might be an incomplete policy, as companies would find alternative mechanisms other than legal protections to defend against appropriation.