Many web sites collect reviews of products and services and use them provide rankings of their quality. However, such rankings are not personalized. We investigate how the information in the reviews written by a particular user can be used to personalize the ranking she is shown. We propose a new technique, topic profile collaborative filtering, where we build user profiles from users’ review t...

Background In 2003 the Wall Street Journal (WSJ) introduced its Monthly Economic Forecasting Survey. Each month the WSJ polls between 50 and 60 well-known economic experts asking their forecasts of future key economic variables such as GDP, inflation, US treasury rates, unemployment, housing starts, and other data. The forecasts are always for set times of the year, namely the ends of the first...

Isolated premature mammary gland enlargement, or precocious thelarche (thelarche praecox, t.p.), is a glandular tissue development which occurs in girls below eight years of age without any other symptoms of systemic estro− gen activity. T.p. is usually observed during the first two to three years of life. Ethnic and nutritional factors influ− ence the frequency of t.p. incidence. T.p. is conne...

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 proce...

We study a model where a decision maker (DM) must select an adviser to advise her about an unknown state of the world. There is a pool of available advisers who all have the same underlying preferences as the DM; they differ, however, in their prior beliefs about the state, which we interpret as differences of opinion. We derive a tradeoff faced by the DM: an adviser with a greater difference o...