مقاله انگلیسی رایگان در مورد سهام مشترک، نظریه بازی و اصل دلبستگی منطقه ای (الزویر)

Many fish stocks around the world migrate across international boundaries and are, therefore, shared among two or more nations. This is the case in particular in the Northeast Atlantic. The migratory pelagic stocks (herring, mackerel, blue whiting) traverse the economic zones of four countries (Iceland, Norway, the Faeroe Islands and the pre-Brexit EU) as well as the high seas in between. Agreements on managing these stocks have been concluded between the countries concerned, but some of these have periodically broken down, due to changes in the migrations of the stocks involved. This happened with respect to the mackerel stock after it began to appear in the Icelandic economic zone in significant quantities in 2007. The agreement was partially restored in 2014, but Iceland and Greenland are still not part of it (in recent years mackerel has been encountered in the Greenlandic economic zone). A situation where management agreements of shared stocks break down, or the absence of such agreements, calls for a game-theoretic analysis. For non-economists, “game theory” sounds frivolous, to the point of not deserving to be taken seriously. This is unfortunate, because game theory is a serious matter indeed, dealing with the strategic interaction among firms, individuals or countries where the outcome of decisions made by one agent depends on the decisions made by other agents, implying that one particular agent had better take into account what the others might do.1 Problems of strategic interaction can, however, be posed in several ways, and the outcome can be critically dependent on how the problem is framed. Two such approaches will be discussed in this paper. One is the Nash-Cournot game where each player takes decisions based on hypotheses about what other players will do. Assuming full information, it makes sense to look at an outcome where the hypothetical actions of all players are the best responses to what all others do. Despite the impeccable and appealing logic of this framework it can lead to extremely destructive competition which we do not typically see being realized.