Externalidade positiva

Externalidade positiva em decorrência da contratação de Thomas Sargent, ganhador do Nobel de Economia em 2011, para a New York University:

Sargent deliberated for months before making a decision. Nonetheless, word had gotten out in the field that he was taking N.Y.U.'s offer seriously. Ennio Stacchetti, an old colleague of Sargent's, received a phone call from Sargent ''strongly hinting that he was on his way to N.Y.U.'' Stacchetti promptly accepted his own offer from N.Y.U. John Leahy at Boston University did likewise. For Gianluca Violante, a young macroeconomist, what transpired among the recruits was ''a critical-mass effect.

Economists like to think of it as a 'coordination equilibrium,' in which one person's independent decision is affected by the decisions of others around him. In other words, something big was going on.'' Violante, the only untenured academic among the eight new faculty members, turned down an offer of tenure at the London School of Economics for an office next to Sargent. Most of the new hires were already leaning heavily toward coming to N.Y.U. before Sargent made his interest apparent. Some were eager to live in New York; most said they felt that N.Y.U. was a step up from the departments they were leaving; one is said to have feuded with a dean at his former job. Still, Sargent's name was an enormous draw, the way that teaming with Michael Jordan at his peak would have been for basketball players in quest of a championship.

One economist after another told me that the most important factor in deciding to take a job -- far more important than salary, which tends not to vary much from one top program to another -- is the quality of colleagues. ''You can't just go out and buy people,'' Benhabib says. ''Productive people want to conquer the world. They want to make a mark in research, and they need to interact with others to do that.''