We extend the Gibbard-Satterthwaite theorem in the following way. We prove that an onto, non-dictatorial social choice rule which is employed to choose one of at least three alternatives is safely manipulable. This means that on occasion a voter will have an incentive to make a strategic vote and know that he will not be worse off regardless of how other voters with similar preference orders would vote, sincerely or not. |
Keywords
Social choice rule, strategic overshooting, strategic undershooting, safe manipulation, unsafe manipulation.
Math Review Classification
Primary 91B12
Last Updated
9 July 2008
Length
25 pages
Availability
This article is available in: