Question: Consider this excerpt from the Newsweek article, then classify this description according to one of the models of power structure: "The Fed's evolving crisis-management playbook underscores not only the move toward more public-private collaboration on big global issues, but also the concentration of power among a very select and insular group of players-in this case, the heads of the world's biggest financial institutions, as well as gatekeepers like Bernanke and Paulsen."