Using mechanism design to prevent false-name manipulations
Mechanism design, which is based on game theory, concerns the study of how to design mechanisms that result in good outcomes even when the agents act strategically. The issue of false-name manipulation can be addressed using techniques from mechanism design. The difficulty of designing a good false-name-proof voting rule should be apparent. One may conjecture that votes are necessarily entirely meaningless in this context, and that one might as well choose the winning alternative randomly without regard to the votes. A nontrivial false-name-proof mechanism called the Minimal Bundle (MB) mechanism can be thought of as an improved version of the Set mechanism. An auction mechanism consists of an allocation rule and a payment rule. The assumption that a manipulator can obtain an unlimited number of identifiers at no cost is not realistic. A simple way of addressing the issue of false-name manipulation is to verify that all the identifiers correspond to real agents in the real world.