Valence-Romans' CNAF “Optimal Fair Matching” Algorithm for Daycare Place Allocation

Public daycare (crèche) places are scarce in France — fewer than two places for every ten children under three nationally — and allocation traditionally relied on a municipal committee scoring applications, a process long suspected of favouring well-connected families.

CNAF researchers, through its ISAJE programme, partnered with Valence Romans Agglo to convert existing allocation criteria into a computerised 'student-optimal fair matching' algorithm — a variant of the Gale-Shapley deferred-acceptance mechanism — guaranteeing no lower-priority family could take a place from a higher-priority family who preferred it.

Because the pandemic prevented the human allocation committee from meeting in person, the May 2020 round was run entirely by the algorithm for the first time in France, satisfying 400 of 1,014 applications (39.4%) submitted for that cycle; the algorithm's proposed distribution was then reviewed and formally validated by the agglomeration's allocation commission before places were confirmed.

Coverage of the pilot notes it addressed only one allocation round in one municipality, with no published before/after comparison against the discretionary system it replaced, and some local officials elsewhere in France voiced concern about losing decision-making discretion.