The traditional model of sequential decision making, for instance, in extensive form games, is a tree. Most texts define a tree as a connected directed graph without loops and a distinguished node, called the root. But an abstract graph is not a domain for decision theory. Decision theory...

This paper provides a self-contained definition and a characterization of the class of extensive form games that are adequate for applications, but still do not employ any finiteness assumptions. In spite of its simplicity, the resulting definition is more general than the classical ones....

The Bertrand paradox holds that price competition among at least two firms eliminates all profits in equilibrium, when firms have identical constant marginal costs. This assumes that the number of competitors is common knowledge among firms. If firms are uncertain about the number of their...

Consider a market where an informed monopolist sets the price for a good or asset with a value unknown to potential buyers. Upon observing the price, buyers may pay some cost for information about the value before deciding on purchases. To restrict buyer beliefs we generalize the idea of the...