Implementation by self-relevant mechanisms

We consider implementation by self-relevant mechanisms, where each agent announces only his own preferences together with an outcome, in the general environment. Self-relevancy of mechanisms is desirable from the viewpoint of decentralization on mechanisms. We provide necessary and sufficient conditions for social choice correspondences to be implementable by self-relevant mechanisms. Comparing these conditions with necessary and sufficient conditions for implementation by mechanisms without any restriction, we investigate the effect of self-relevancy on implementability. (C) 2001 Elsevier Science B.V. All rights reserved.