Computers are different from hammers because, unlike hammers, they can operate autonomously, manipulate symbols, and modify themselves. This paper analyzes the factor behind the phenomenon of the de-materialization of advanced economies: combinations of electronic hardware and software; considers...

This chapter provides a survey of the recent work on learning in the context of macroeconomics. Learning has several roles. First, it provides a boundedly rational model of how rational expectations can be achieved. Secondly, learning acts as a selection device in models with multiple REE...

We consider k agents who have different subjective probabilities and are utility maximizers. A planner, who knows the beliefs of the agents, maximizes the social expected utility, which is increasing and symmetric in the utilities of the agents. She does that by optimally stopping the flow of...