Robust group strategy‐proofness

Strategy‐proofness (SP) is a sought‐after property in social choice functions because it ensures that agents have no incentive to misrepresent their private information at both the interim and ex post stages. Group strategy‐proofness (GSP), however, notion applied stage but not stage. Thus, we propose new of GSP, coined robust group (RGSP), which benefits by deviating from truth telling We show for provision public good Minimum Demand rule (Serizawa (1999)) satisfies RGSP when production possibilities set particular topological property. In problem allocating indivisible objects, an acyclicity condition on priorities necessary sufficient Deferred Acceptance satisfy RGSP, only Top Trading Cycles rule. For allocation divisible goods among with single‐peaked preferences (Sprumont (1991)), free disposal, replacement monotonic rules within class sequential allotment RGSP.