Combining Expert Opinions∗

I analyze a model of advice with two perfectly informed experts and one decision maker. The bias of an expert is her private information. I show that consulting two experts is better than consulting just one. In the simple “peer review” mechanism, the decision maker receives just one report, and the second expert decides whether to block the first expert’s report. A more rigid peer review process improves information transmission. Simultaneous consultation transmits information better than sequential consultation and peer review. However, peer review achieves significant information transmission, with the decision maker receiving only one report. There is an asymmetric equilibrium that is more efficient than the symmetric equilibrium. When given the chance to discover biases of experts, the decision maker may prefer not to do so. ∗I thank my advisor, Larry Samuelson, for helpful discussions and continuous support. I am also grateful to Bill Sandholm for very useful suggestions. Thomas Gilligan, Eric Rasmusen, and seminar participants at Indiana University (BEPP), University of Wisconsin, and WEA Meeting in Taipei have provided helpful comments. Any remaining mistakes are my own. †Department of Economics, University of Wisconsin, Madison. Email: [email protected].