Affirmative action and school choice

This paper studies a way of introducing affirmative action in the school choice problem to implement integration policies. The paper proposes the use of a natural two-step mechanism. The (equitable) first step is introduced as an adaptation of the deferred-acceptance algorithm designed by Gale and Shapley, when students are divided into two groups. The (efficient) second step captures the idea of exchanging places inherent to Gale's top trading cycle.