[This item is a preserved copy. To view the original, visit http://econtheory.org/] Strategy-proofness, requiring that truth-telling be a dominant strategy, is a standard concept in social choice theory. However, this concept has serious drawbacks. In particular, many strategy-proof mechanisms...

In n-agent exchange economies, we show that all efficient and continuous rules are "diagonally dictatorial" over the restricted domain of linear preferences and, in the 2-good case, over the domain of homothetic preferences. The diagonal dictator receives the entire endowment whenever all agents...