Antonio Jiménez-Martínez e Isabel Melguizo-López, Profesores Investigadores Titulares de la División de Economía del CIDE, escribieron el documento de trabajo Making Friends: the Role of Assortative Interests and Capacity Constraints.   Abstract We investigate the properties of stability and efficiency of friendship networks when individuals (i) have arbitrary levels of assortative interests and (ii) are capacityconstrained