Game Theory and Democracy


What is democracy? More specifically, how does one create rules for elections which have outcomes most consistent with democratic values? The magnitude of the game theory of the single vote ballot in democracies that use it is huge: the two party system, the need for political primaries, obstacles facing 3rd party candidates, and how voters are “throwing their votes away” when they vote for them. This is not inherent to democracy. This is the game theory of the single vote ballot. Alternatively, using preferential ballots in elections is a natural idea since it allows voters to express a 1st choice, a 2nd choice, a 3rd choice, etc. on each ballot, thereby collecting more information from each voter and creating the potential for an outcome which better represents the voters. However, there are many ways to determine the winner of a preferential ballot election, and each “preferential ballot vote counting method” has its own game theory, both for the candidates and the voters, some better and some worse, and often very different from the game theory of the single vote ballot. So which preferential ballot vote counting method is the best? Does there exist a vote counting method which incentivizes politicians to seek out centrist, consensus building positions and to focus on issues important to voters, more than game theoretic tactics meant to manipulate the electorate? Or is there another goal we should be pursuing? In this course, we’ll use game theory and mathematics to study these questions.

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