Sunday 31 July 2011

On the accessibility of the core (Review)


This paper by Yang (2010) belongs to a recent wave of literature that study the core of a cooperative game as a dynamic concept. Sengupta and Sengupta (1996) have shown that from any imputation the core can be accessed by a finite number of blocks. Kóczy (2006) provided an alternative blocking sequence and showed that the number of blocks required is bounded. The present paper relies on the proof of Sengupta and Sengupta by using z-dominance and provides an explicit bound on the length of z-dominance paths: the number of active coalitions, that is, coalitions with a payoff higher than the sum of their members' individual payoffs.


Monday 25 July 2011

LGS7 - Part I.: Salles on the impossibility of liberalism


I am often annoyed if I miss an interesting conference.  In this post I report on LGS7 – the 7th Conference on Logic Game Theoryand Social Choice, held last week in Bucharest. Of course this post will not help me with missed conferences, but hopefully other game theorists will find them interesting.
There are two types of conferences. The big ones, like the EEA-ESEM meetings, where you can network with a lot of new people, but honestly, with most of them, you are not likely to meet ever again. There are also the small, field conferences, where there is always the risk that you meet all the same people as last year (this can also be nice, too), who give a talk you already know. LGS is the third kind, as it collects people from different disciplines (logicians, game theorists, social choice theorists, but also sociologists, computer scientists) with very specialised interests. As it is organised biannually, it is also unlikely that you will hear an updated version of what you have heard last year.