Processing Reserves Simultaneously

Reserve systems allow combining competing objectives to allocate scarce resources based on priority. For example, schools may reserve some seats for students from underprivileged backgrounds or hospitals may reserve some ventilators for frontline healthcare workers. An important determinant of the outcome is the order in which reserve categories are processed: categories processed later generally matter more than those processed earlier. The reason is that an agent who qualifies for multiple categories counts towards the quota of whichever category is processed first. I propose a new solution that processes reserve categories simultaneously so that if an agent qualifies for n categories, she takes 1/n units from each of them. That approach treats categories symmetrically and offers greater transparency: the relative importance of categories is entirely captured by the size of their quotas.