Instructions:
Move a vote from q>p>r to q>r>p (or back) by clicking on the “Change Vote” button below. What happens to the winner if one voter makes this change?
Repeat the experiment with the “Mean” button selected below the simulation. How does the situation differ?
▷ Explanation:
The q>p>r voter initially votes sincerely, and p is elected. Clicking the “Change Vote” button switches her ballot to the insincere q>r>p, and achieves a win for her most favored alternative q. This switch is thus a “strong” McBorda manipulation with 5 voters (the fewest possible).
Toggling to the Mean position shows that the same switch yields a Borda manipulation as well, but it is of the “weak” type, because the sincere vote yields a two-way tie between p and q.
Should a weak manipulation be considered less serious than a strong one? The Crossing Boundaries link (on the right) explores this question, using a variant of the profile you see here.
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