In priority-based matching problems, there is a trade-off between efficiency andreducing justified-envy. We show that finding an efficient and justified-envy minimalmatching is an NP-hard problem when objects have weak priority rankings. Consequently, we focus on resolving the trade-off in a...

School districts commonly ration public school seats based on students preferences and priorities. Priorities reflect the school districts’ objectives for reducing busing costs (walk-zone priority) or utilizing siblings’ learning spillovers (sibling priority). Our work develops a simple...