Allocation Proportionality of OWA--Based Committee Scoring Rules

Researchers have introduced a new measure called 'allocation proportionality degree' to quantify how fairly multi-winner voting rules distribute seats among political parties. The study tests six common systems—including SNTV, k-Borda, and Bloc Voting—against this ideal. It finds no existing rule perfectly satisfies the principle, where a party's share of elected candidates should match its aggregate voter support. This provides a crucial new tool for comparing and potentially reforming electoral systems used in AI governance and beyond.