Filipe Costa de Souza

A Co-authorship network analysis of CNPq’s productivity research fellows in the probability and statistic area

In this paper, we analyzed the co-authorship network between all CNPq’s productivity research fellows in the Probability and Statistics area in Brazil. Our aim was to describe and to understand how network measures influence researchers’ productivity. The data was gathered from the CNPq’s Lattes Platform using the software scriptLattes, and a link between two fellows represents the fact that they wrote an article together from 2009 to 2013. The network is disconnected and has only 4.7% of its possible connections. Through a regression analysis, we were able to infer that the centrality positions of an author matters to his/her productivity. As expected, closeness centrality had a negative effect on fellows’ productivity, while the degree centrality had a positive effect.

Collaborative dominance: when doing unto others as you would have them do unto you is reasonable

In this article, we analyze how reasonable it is to play according to some Nash equilibria if players have a preference for one of their opponents’ strategies. For this, we propose the concepts of collaborative dominance and collaborative equilibrium. First we prove that, when the collaborative equilibrium exists it is always efficient, what can be seen as a focal property. Further we argue that a reason for players choosing not to collaborate is if they are focusing in security instead of efficiency, in which case they would prefer to play maximin strategies. This argument allows us to reduce the hall of reasonable equilibria for games where a collaborative equilibrium exists. Finally, we point out that two-player zero-sum games do not have collaborative equilibrium and, moreover, if there exists a strategy profile formed only by collaboratively dominated actions it is a Nash equilibrium in such kind of game.