We generalize the canonical problem of Nash implementation by allowing agents to voluntarily provide discriminatory signals, i.e. evidence. Evidence can either take the form of hard information or, more generally, have differential but non-prohibitive costs in different states. In such...

How much information should a central bank (CB) have about (i) policy objectives and (ii) operational shocks to the effect of monetary policy? We consider a version of the Barro-Gordon credibility problem in which monetary policy signals an inflation-biased CB's private information on both these...