Method of equal shares

Social choice and electoral systems
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Single-winner methods Single vote – plurality methods First preference plurality (FPP) Two-round (US: Jungle primary) Partisan primary Instant-runoff UK/NZ: Alternative vote (AV) AU: Preferential voting US/CA: Ranked-choice (RCV) Party block voting Plurality block voting Condorcet methods Condorcet-IRV Round-robin voting Minimax Kemeny Schulze Ranked pairs Maximal lottery Positional voting Plurality (el. IRV) Borda count (el. Baldwin, Mdn. Bucklin) Antiplurality (el. Coombs) Rated (cardinal) voting Score voting Approval voting Combined approval voting Majority judgment STAR voting
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Mixed systems By results of combination Mixed-member majoritarian Mixed-member proportional By mechanism of combination Non-compensatory Parallel (superposition) Coexistence Conditional Fusion (majority bonus) Compensatory Seat linkage system UK: 'AMS' NZ: 'MMP' Vote linkage system Negative vote transfer Mixed ballot Supermixed systems Dual-member mixed proportional Rural–urban proportional Majority jackpot By ballot type Single vote Double simultaneous vote Dual-vote
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Social and collective choice Impossibility theorems Arrow's theorem Majority impossibility Moulin's impossibility theorem McKelvey–Schofield chaos theorem Gibbard's theorem Positive results Median voter theorem Condorcet's jury theorem May's theorem Condorcet dominance theorems Harsanyi's utilitarian theorem Non-classical mechanisms VCG mechanism Quadratic voting Supermajority Unanimity
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The method of equal shares (MES) is a participatory budgeting algorithm specifically designed to guarantee extended justified representation (a form of proportional representation). It was originally developed for committee elections (under the name Rule X). It was later adapted to participatory budgeting (PB) and to simultaneous public decisions. It can be used with any available ballot format, including approval ballots, ranked ballots or cardinal ballots. MES has been used for participatory budgeting in various European cities.

MES can be described as a member of a class of voting methods called expanding approvals rules introduced earlier in 2019 by Aziz and Lee for ordinal preferences (that include approval ballots).