Speaker: Arkadii Slinko (Department of Mathematics, UOA)
Title of presentation: “Generalisation of the Danilov-Karzanov-Koshevoy construction for Peak-Pit Condorcet domains”
Date, Time and Venue: Wednesday, 4 March 2020, 14:30-15:30, 260-5115 [Business School Building, Level 5]
Abstract: Danilov, Karzanov and Koshevoy (2012) geometrically introduced an interesting operation of composition on Condorcet domains and using it they disproved a long-standing problem of Fishburn about the maximal size of connected Condorcet domains. We give an algebraic definition of this operation and investigate its properties. We give a precise formula for the cardinality of composition of two Condorcet domains and improve the Danilov, Karzanov and Koshevoy result showing that Fishburn’s alternating scheme does not always produce a largest connected Condorcet domain.
27th November 2019, 2-4pm, room 303-G014 (Science building)
To attend, please RSVP here
||Welcome by the Theme Leader
Steven Galbraith (UoA, Mathematics)
|2:15pm – 3.45pm
||CMSS Members – Lightning Talks
- Simona Fabrizi (UoA, Economics): Voting under ambiguity
- Matthew Ryan (AUT, Economics): Mathematical psychology and the algebra of choice
- Arkadii Slinko (UoA, Mathematics): Condorcet Domains
- Patrick Girard (UoA, Philosophy): Facing the inevitable: avoiding, tolerating, or embracing inconsistency
- Steffen Lippert (UoA, Economics): Transfers and climate cooperation
- James Tremewan (UoA, Economics): An overview of my ongoing research using experimental methods in social science
- Thomas Pfeiffer (New Zealand Institute for Advanced Studies (NZIA), Massey University): Predict to decide: Decision markets in theory, experiments and real-world implementations
CMSS Affiliated Postgraduate Students – More lightning talks
- Michael Gordon (PhD Candidate, Massey University): Large-scale forecasting in the DARPA SCORE project
- Wenlong (Stan) Wang (PhD Candidate, Massey University): Towards implementing a decentralized decision market application
- Yen Ling Tan (Honours student, UoA): Consumer decision-making under uncertainty on digital platforms
|Discussion on future activities of the CMSS and/or Knowledge Sciences Theme
Chair: Steven Galbraith (UoA, Mathematics)
||Drinks and discussions
The CMSS is hosting the 2019 edition of the event. Visit this website to know more about the event. Everyone welcome to join any of the sessions planned for this meeting!
Speaker: Yi-Hsuan Lin (Academia Sinica, Taipei)
Paper to be presented: “Stochastic Choice and Rational Inattention”
Date, Time and Venue: Wednesday, 23 October 2019, 15:00-16:00, 260-5115 [Business School Building, Level 5]
Abstract: We consider a decision maker who first chooses an information structure, and then chooses an action after receiving a signal. The cost of information may be either material or cognitive and is unobserved. Thus, cost must be inferred from observable behavior. We assume that the choice of action is observed, but the choice of information is not. Due to the unobservability of the acquired private information, the choice of action appears random from an outside analyst’s point of view. We show that, given only stochastic choice from menus of actions, an analyst can identify the agent’s taste (risk attitude), prior belief, and information cost function. Identification of the cost function from behavior stands in contrast with the large literature on applications of the rational inattention model where the functional form of the cost function is assumed known by the analyst (Sims 2003). In addition, we discuss the behavioral implications of our model which are weaker than some key properties of random expected utility models. In particular, the property of Monotonicity (the addition of a new action cannot increase the probabilities of choice of the existing actions) is violated in our model because of the endogeneity and hence menu-dependence of private information. However, two axioms that jointly weaken Monotonicity are satisfied. Finally, we provide necessary and sufficient conditions for stochastic choice to be rationalized by our model.
Speaker: Arkadii Slinko (University of Auckland)
Paper to be presented: “Secret Sharing and Prisonner’s Dilemma” joint with Yvo Desmedt (University of Texas at Dallas)
Date, Time and Venue: Wednesday, 21 August 2019, 15:00-16:00, 260-5115 [Business School Building, Level 5]
Abstract: The study of Rational Secret Sharing initiated by Halpern and Teague (2004) regards the reconstruction of the secret in secret sharing as a game. It was shown that participants (parties) may refuse to reveal their shares and so the reconstruction may fail. Moreover, a refusal to reveal the share may be a dominant strategy of a party. In this paper we consider secret sharing as a sub-action or subgame of a larger action/game where the secret opens a possibility of consumption of a certain common good. We claim that utilities of participants will be dependent on the nature of this common good. In particular, Halpern and Teague (2014)’s scenario corresponds to a rivalrous and excludable common good. We consider the case when this common good is non-rivalrous and non-excludable and many natural Nash equilibria. We list several applications of secret sharing to demonstrate our claim and give corresponding scenarios. In such circumstances the secret sharing scheme facilitates a power sharing agreement in the society. We also state that non-reconstruction may be beneficial for this society and give several examples.
Speaker: David Kelsey (University of Exeter)
Paper to be presented: “Tort Liability and Unawareness” joint with Surajeet Chakravarty (Exeter University, UK) and Joshua Teitelbaum (Georgetown University, USA)
Date, Time and Venue: Wednesday, 14 August 2019, 15:00-16:00, 260-5115 [Business School Building, Level 5]
Abstract: Unawareness is a form of bounded rationality where a person fails to conceive all feasible acts or consequences or to perceive as feasible all conceivable act-consequence links. We study the implications of unawareness for tort law, where relevant examples include the discovery of a new product or technology (new act), of a new disease or injury (new consequence), or that a product can cause an injury (new link). We argue that negligence has an important advantage over strict liability in a world with unawareness-negligence, through the stipulation of due care standards, spreads awareness about the updated probability of harm.
Speaker: Michael Gordon (PhD Candidate, Massey University)
Paper to be presented: “Can we predict outcomes of systematic replication studies? Decision Markets Part 2 – Real World Applications”
Date, Time and Venue: Monday, 27 May 2019, 14:00-15:00, 260-6115 [Business School Building, Level 6]
Abstract: The credibility of scientific findings is of fundamental importance to enhance future research. One potential approach of collecting information about this credibility is to elicit beliefs about the reproducibility of scientific claims among scientists. Four studies have recently used surveys and prediction markets to estimate beliefs about replication in systematic large scale replication projects, but the sample size in each study has been small. Here we pool data for the four studies (n = 104) to assess the performance of surveys and prediction markets. This dataset and subsequent analysis allow us to comment on the real world success of prediction markets in terms of eliciting and aggregating information.
Speaker: Thomas Pfeiffer (NZIAS, Massey University)
Paper to be presented: “Predict to decide: An Introduction to decision markets”
Date, Time and Venue: Monday, 20 May 2019, 14:00-15:00, 260-6115 [Business School Building, Level 6]
Abstract: Prediction markets are popular tools to “crowd-source” distributed information and aggregate it into forecasts. Such forecasts can be very valuable for decision makers. Commercial companies, for instance, can benefit from accurate forecasts regarding the future demand for their products. Many decision-making problems, however, require conditional forecasts. To decide, for instance, between alternative marketing campaigns, a company needs to understand how each of the alternatives will affect sales. Finding mechanisms that properly incentivise participants to provide their information for such conditional forecasts is non-trivial, but can be done through so-called decision markets. I will kick off a mini-series on decision markets by describing how they work and giving an overview of our research activities on this topic.
Speaker: Matthew Ryan (AUT)
Paper to be presented: “Rationalising Random Choice as Random Consideration”
Date, Time and Venue: Monday, 13 May 2019, 14:00-15:00, 260-6115 [Business School Building, Level 6]
Abstract: Attempts to rationalise experimental evidence of pervasive randomness in choice behaviour may be divided into four categories: (i) models of deliberate randomisation; (ii) models of noisy utility maximisation (bounded rationality); (iii) random preferences models; and (iv) random consideration models. Category (i) has largely been explored by economists; (ii) and (iii) are mainly associated with mathematical psychologists and (iv) with researchers in marketing science. Recently, economists have taken an increasing interest in (iv), following the pioneering work of Manzini and Mariotti (Econometrica, 2014). This talk will briefly introduce random consideration models and their relationships with random preference models. A new random consideration model will also be proposed and “axiomatised”. This new model allows preferences to be ill-behaved on subsets of alternatives that are never considered together. In other words, the model is predicated on the implicit (and hopefully plausible) assumption that consideration is necessary to discipline preference.
Speaker: Mariya Teteryatnikova (Department of Economics at the National Research University Higher School of Economics, Moscow)
Paper to be presented: “On the Existence of Perfect Pairwise Stable Weighted Networks” joint with Philippe Bich (Paris School of Economics and University of Paris 1 Pantheon-Sorbonne)
Date, Time and Venue: Monday, 6 May 2019, 14:00-15:00, 260-6115 [Business School Building, Level 6]
Abstract: We introduce a new concept of stability in network formation, perfect pairwise stability, and prove that a perfect pairwise stable network exists under very general assumptions. Perfect pairwise stability strictly refines the pairwise stability concept of Jackson and Wolinsky (1996), by transposing the idea of “trembling hand” perfection from non-cooperative games to the framework of cooperative pairwise network formation. The existence result extends that of Bich and Morhaim (2017). We prove that our concept is distinct from strong pairwise stability, a refinement concept introduced by Jackson and Van den Nouweland (2005). We also introduce a sequential framework for network formation and define a natural concept of sequential pairwise stability. By analogy with non-cooperative games, we prove that the sequential framework can be associated with a static one, and that the sequential pairwise stable networks correspond exactly to perfect pairwise stable networks in the static framework.
Short Bio: Mariya Teteryatnikova received her PhD in 2010 from the European University Institute in Florence, Italy. After that, she worked for six years as an Assistant professor at the University of Vienna and for another year at WU- Vienna University of Economics and Business. Since September 2017 she holds a position of an Assistant professor at Higher School of Economics in Moscow and since July 2018 – also a position of a Research associate at WU in Vienna. Her main research fields are (mostly applied) game and network theory and industrial organization.