Frank Morgan's Math Chat


July 6, 2000

The Winning Voting System

In last time's little survey among the following voting systems:

ranking got the most first-place votes, but using the ranking system, runoff won. But using the runoff system, approval voting won. But using approval voting, runoff won. So I guess perhaps runoff is the winner, although no method won under its own system!

Watch for the complete story in the article by Dana Mackenzie in the November issue of Discover magazine.

Old Challenge. Design your own voting system.

Winning Answers. Joseph DeVincentis suggests a version of approval voting in which each voter has three choices: approval (+1), no opinion (0), or disapproval (-1), and the highest sum wins.

Justin Smith would count votes plus IQ minus the amount of money spent.

New Challenge (Matthias Weber). How can two people determine which is older without revealing their ages? No outside help is permitted. You may assume that their ages are different.

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Copyright 2000, Frank Morgan.