Ranked pairs

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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
Proportional representation Party-list Apportionment Highest averages Largest remainders National remnant Biproportional List type Closed list Localized list Open list Free list No list Quota-remainder methods Single transferable vote (Hare, Droop) Schulze STV CPO-STV Quota Borda Approval-based committees Thiele's method Phragmen's method Expanding approvals rule Method of equal shares Fractional social choice Direct representation Interactive representation Liquid democracy Fractional approval voting Maximal lottery Random ballot Semi-proportional representation Cumulative SNTV Limited voting Plurality block voting
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 proportional Rural–urban proportional Majority jackpot By ballot type Single vote Double simultaneous vote Dual-vote
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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Ranked Pairs (RP), also known as the Tideman method, is a ranked voting method that determines a single winner from ballots that rank candidates in order of preference. The method is like a round-robin tournament in that it examines every possible pairing of one candidate against another.

The ballots are used to determine the winner in any race with just two candidates, based upon which of the two candidates is ranked higher on each ballot. If there is a candidate who wins regardless of whom they are paired against then that candidate is elected the winner. If there is no candidate who wins every pairing then the pairings with a more decisive win dominate those that are less decisive. For example, if Paper beats Rock, Rock beats Scissors, and Scissors beats Paper; and it is the case that the first two wins are more decisive than the third, then the third is ignored and Paper is elected the winner by virtue of winning their remaining pairings.

This system of ranked voting was first proposed by Nicolaus Tideman in 1987. Unlike Instant Runoff Voting, Ranked Pairs is guaranteed to satisfy the Condorcet winner criterion, meaning that any candidate who beats every other candidate, in a one-on-one race between the two, will be elected the winner.