Working Paper: NBER ID: w14864
Authors: Atila Abdulkadiroglu; Parag A. Pathak; Alvin E. Roth
Abstract: The design of the New York City (NYC) High School match involved tradeoffs among efficiency, stability and strategy-proofness that raise new theoretical questions. We analyze a model with indifferences--ties--in school preferences. Simulations with field data and the theory favor breaking indifferences the same way at every school --single tie breaking-- in a student-proposing deferred acceptance mechanism. Any inefficiency associated with a realized tie breaking cannot be removed without harming student incentives. Finally, we empirically document the extent of potential efficiency loss associated with strategy-proofness and stability, and direct attention to some open questions.
Keywords: matching; strategyproofness; efficiency; indifferences; school choice
JEL Codes: C78; D60; I20
Edges that are evidenced by causal inference methods are in orange, and the rest are in light blue.
| Cause | Effect |
|---|---|
| single tie-breaking (C78) | improved student welfare (I39) |
| multiple tie-breaking (C78) | decreased student welfare (I39) |
| relaxing stability constraints (C62) | improve match outcomes (C78) |
| single tie-breaking (C78) | higher number of students receiving top choice (I23) |
| inefficiency associated with tie-breaking (D61) | compromises student incentives (D29) |
| trade-off between strategyproofness and efficiency (D61) | impacts student assignments (I24) |
| lack of strategyproof mechanism (D79) | limits pareto improvement (D61) |