Election results also depend… on the voting process. “Mathematicians are well aware that for any given situation, changing the function is enough to modify the result,”explains Antoinette Baujard, professor of economics1. “When the function is a voting method, it is also necessary to understand how the results may differ and which criteria should be used to compare different systems.”Since the end of the 1990s, research into the techniques and protocols used to test and correlate voting procedures has given rise to various experiments, starting with the 2002 presidential election.
Approval and ranked-choice ballot, or voting based on different ranking scales… The “Voter Autrement 2017” (“Vote Differently 2017”) project specifically sought to study the effect of using various scoring scales. The results—even after participation biases were corrected—should be interpreted with caution but the data gathered is none the less useful for comparing several methods. “Analysis highlights the tactical voting phenomenon, the acceptance of new systems by voters and the satisfaction of expressing a point of view as a citizen,”sums up Antoinette Baujard.
“Voting science began before the French Revolution with Borda, Condorcet and Laplace,”observes Rida Laraki, CNRS senior researcher2 at the Université Paris Dauphine. Following an experiment conducted at Orsay in 2002, he invented and developed the so-called “majority judgement” mathematical theory, in collaboration with Michel Balinski, CNRS senior researcher emeritus3. People vote by giving their opinion of candidates using the term of their choice—”very good”,“average”,“rejected”, etc. The winner is the contender with the highest ranking as approved by a majority of the electorate.
This method was tested from 2007 onwards and presented in Majority Judgement4. It was used in 2016 in a primary pollin which 33,000 voters designated a candidate on LaPrimaire.org, a digital platform secured throughblockchain technology. The lucky winner only obtained 135 endorsements but “the platform was reused during the 2017 presidential election to test majority judgement over the two rounds with 53,000 voters taking part. The interest this generated led to the creation of the ‘Mieux Voter’ (‘Vote Better’) Association to promote this system,”notes Rida Laraki.