Candidate Archive

The archive intentionally retains some proxy-dominated candidates because they can still have strong PPA. On bp_multi, the grid-based archive retained far more candidates than the non-dominated archive, including candidates behind the proxy frontier. DOPP creates a diverse candidate set using simulated annealing and a grid-based Pareto archive over proxy space. The archive keeps at most one representative in each grid cell and replaces it only when a new solution is at least as good in both proxy metrics. DOPP cannot recover high-quality PPA candidates that are absent from the generated candidate set.