Manipulability of Voting Systems

Read the book chapters first, then make sure you can answer the questions in the notes. Following that, work on some skills-check problems and exercises. Then take the online quizzes.

Reading

10.1-10.4

Skills Check

7, 11, 13, 15, 27

Exercises

7, 9, 10, 11, 16, 18, 19, 23, 24

Quiz

No quiz this week

10.1

• When precisely do we say that a voting system is manipulable?

10.2

• Explain why Condorcet’s Method is non-manipulable.

10.3

• Show that the Borda Count on 3 candidates is non-manipulable, but on 4 or more candidates it is manipulable.
• Show that the Hare system is manipulable.
• Show that the Sequential Pairwise Voting system is manipulable.

10.4

• What does the Gibbard-Satterwaite Theorem say?