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Rida Laraki: Majority Judgment; An Alternative to Paradoxes in Voting

There is a growing sense that the electoral systems used throughout the world - the UK's and USA's first-past-the-post, France's "two-past-the-post", Australia's and Ireland's STV, and others - are not satisfactory. So, why not simply change them?
Regrettably, the traditional "social choice" theory has been unable to propose a viable system of voting. Why? Because, since Ramon Llull in 1299 and Nicolas Cusanus in 1433, the model of voting has remained exactly the same, and leads to paradoxes, impossibilities and incompatibilities that cannot be overcome, and notably Arrow's "impossibility theorem", and Condorcet's paradox.
Majority Judgement is a new alternative - whose antecedents may be traced to the Marquis de Laplace and Sir Francis Galton - that sees the problem and models it differently. In the new paradigm, Arrow's theorem says that there is no satisfactory mechanism unless there is a common language of measuring the merits of the candidates. But when a common language exists - and practice and experimental evidence show they do exist and can be defined - then one mechanism meets the most important properties: the majority judgement.

Lecture 1. Majority Judgment in theory
Why traditional voting systems and the model on which they are based are inadequate is explained. Majority judgement's principal properties are then presented: it best resists manipulation, is not subject to Arrow's impossibility, nor to Condorcet's paradox.

Lecture 2. Majority Judgment in practice
Realistic data from skating and French presidential elections allow to compare different voting methods with majority judgment: Condorcet's and Borda's classical proposals, point-summing methods, first-past-the-post and approval voting.

If time is left; answer to some critics:
Majority judgment admits the no-show paradox. We show why it is relatively unimportant and why the only way of avoiding it implies using a worse system.

- Arrow, K. J. (1951), Social Choice and Individual Values, Yale University Press.
- Balinski, M. et R. Laraki (2010), Majority Judgment: Measuring, Ranking, and Electing, MIT Press.
- Brams, S. J. et P. C. Fishburn (1983), Approval Voting, Boston: Birkh¨auser.
- Moulin, H. (1988), Axioms of Cooperative Decision-Making, Monograph of the Econometric Society, Cambridge University Press