Leveling seat

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Single-winner methods Single vote Plurality rule First preference plurality (FPP) General ticket Majority rule Two-round Nonpartisan primary Partisan primary Instant-runoff UK: Alternative vote (AV) US: Ranked-choice (RCV) Supermajority Consensus Unanimity Condorcet methods Condorcet-IRV Round-robin voting Minimax Kemeny Schulze Ranked pairs Maximal lottery Positional voting Plurality (el. IRV) Borda count (el. Baldwin, ) Antiplurality (el. Coombs) Cardinal voting Score voting Approval voting STAR voting Median voting Majority judgment Graduated Median voting rule Bucklin voting
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Paradoxes and pathologies Spoiler effects Spoiler effect Cloning paradox Frustrated majorities paradox Center squeeze Pathological response Perverse response Apportionment paradox Best-is-worst paradox No-show paradox Multiple districts paradox Strategic voting Lesser evil voting Exaggeration Truncation Turkey-raising Wasted vote Paradoxes of majority rule Tyranny of the majority Discursive dilemma Conflicting majorities paradox
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 VCG mechanism Quadratic voting
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Leveling seats (Danish: tillægsmandat, Swedish: utjämningsmandat, Norwegian: utjevningsmandater, Icelandic: jöfnunarsæti, German: Ausgleichsmandat), commonly known also as adjustment seats, are an election mechanism employed for many years by all Nordic countries (except Finland) in elections for its national legislatures. Germany also used national leveling seats for its legislature's lower chamber, the Bundestag, from 2013 to 2023. Leveling seats are seats of additional members elected to supplement the members directly elected by each constituency. The purpose of the additional seats is to ensure that each party's share of the total seats is roughly proportional to the party's overall shares of votes at the national level.