Download the Study

Changing the Boston School Choice Mechanism:  Strategy-proofness as Equal Access

Why Change School Choice Mechanisms?

School Assignment, May 2006

In a closer examination of the school choice mechanism previously used by Boston Public Schools, Abdulkadiroglu, Pathak, Roth, and Sönmez establish an empirical case against the previous Boston mechanism in favor of a change to a strategy-proof mechanism.  While some parents use sophisticated strategic behavior, others display unsophisticated strategic behavior.  Without knowing the true preferences of a family, there arises a mistake causing families to be disproportionately unassigned.

The  Boston School Committee vot­ed to replace the exist­ing school choice mech­a­nism (the Boston mech­a­nism) with an alter­na­tive mech­a­nism that removes the incen­tives to “game the sys­tem.” This fol­lowed two years of inten­sive dis­cus­sion and analy­sis of the exist­ing school choice sys­tem and the behav­ior it elicit­ed, as well as a dis­cus­sion of two dif­fer­ent pos­si­ble replace­ment school choice mechanisms.

The Boston expe­ri­ence has impli­ca­tions for oth­er school dis­tricts.  There are quite a few oth­er school dis­tricts with stu­dent assign­ment sys­tems shar­ing the main fea­tures of the Boston mech­a­nism – for exam­ple Cambridge, Charlotte-Mecklenberg, Denver, Miami-Dade, Rochester, Tampa-St. Petersburg, and White Plains. Based on our analy­sis of the behav­ior of Boston fam­i­lies, it seems like­ly that in these oth­er school dis­tricts par­ents are faced with solv­ing a com­plex strate­gic prob­lem, rather than just a prob­lem of form­ing pref­er­ences over schools. A strat­e­gy-proof mech­a­nism like the ones pre­sent­ed in this study would lift this strate­gic bur­den from par­ents, and makes the school choice process more trans­par­ent. School choice is often a sen­si­tive polit­i­cal issue, and trans­paren­cy helps to remove some aspects of how to best assign chil­dren to schools from the polit­i­cal are­na to the tech­ni­cal are­na, and clar­i­fy which issues remain to be set­tled by the polit­i­cal process. There will always be such issues, since until there are enough top qual­i­ty school places to sat­is­fy all fam­i­lies, some aspects of school choice will be a dis­trib­u­tive process, with only some stu­dents able to gain admis­sion to the most desir­able schools.