Expanding approvals rule

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The expanding approvals rule (EAR) is a rule for multi-winner elections that guarantees a form of proportional representation called proportionality for solid coalitions. It is a generalization of the highest median rules to include multiwinner elections^[1] and participatory budgeting.^[2] When working with ranked ballots, it is sometimes called the Bucklin transferable vote.^[3] However, the rule can be more effectively implemented using rated ballots, which are easier to use and provide additional cardinal utility information that can be used for better decision-making.