Speaker: Nina Anchugina & Arkadii Slinko
Affiliation: The University of Auckland
Title: Two talks see titles below
Date: Thursday, 7 May 2015
Time: 5:00 pm
Location: Room 260-325, Owen Glenn Building

1. Speaker: Nina Anchugina.
Title: A simple framework for the axiomatization of exponential and quasi-hyperbolic discounting
Time: 30 min.

Abstract: The main goal of this talk is to investigate which normative requirements, or axioms, lead to exponential and quasi-hyperbolic forms of discounting in inter-temporal decision-making. Exponential discounting has a well-established axiomatic foundation originally developed by Koopmans (1960) with subsequent contributions by several other authors. Hayashi (2003) and Olea and Strzalecki (2014) axiomatize quasi-hyperbolic discounting. In this talk we provide an alternative foundation for exponential and quasi-hyperbolic discounting, with simple, transparent axioms and relatively straightforward proofs. Using techniques by Fishburn (1982) and Harvey (1986), we show that Anscombe and Aumann’s (1963) version of Subjective Expected Utility (SEU) theory can be readily adapted to axiomatize the aforementioned types of discounting, in both finite and infinite horizon settings.

This is a joint work with Matthew Ryan.

2. Speaker: Arkadii Slinko
Title: Condorcet Domains and Median Graphs
Time 30 min

Abstract: A set of linear orders D is called a Condorcet domain if every profile composed from preferences from D has acyclic majority relation. Maximal Condorcet domains have been a subject of intense investigation, especially by Fishburn and Monjardet. Demange (2012) generalized the classical single-crossing property to the intermediate property on median graphs and proved that for every intermediate profile R with an odd number of voters on a median graph G there is a representative voter whose preference order coincides with the majority relation. We complement her result with proving that the linear orders of any profile which is intermediate on a median graph form a Condorcet domain. We prove that for any median graph there exists a profile that is intermediate with respect to that graph and that one may need at least as many alternatives as vertices to construct such a profile. We provide a polynomial-time algorithm to recognise whether or not a given profile is intermediate with respect to some median graph.

This is a joint work with Adam Clearwater (The University of Auckland) and Clemens Puppe (Karlsruhe Institute of Technology, Germany).

Everyone welcome!