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 demonstrates that the current literature on cross-ownership among firms underestimates the true degree of separation between cash flow rights and voting rights. We use accounting identities to define coefficients of control, such that any (direct or indirect) control of a firm may be...

Perfect information games have a particularly simple structure of equilibria in the associated normal form. For generic such games each of the finitely many connected components of Nash equilibria is contractible. For every perfect information game there is a unique connected and contractible...

In a two-stage extensive form game where followers can observe moves by leaders only with noise, pure subgame perfect Nash equilibria of the limiting game without noise may not survive arbitrarily small noise. Still, for generic games, there is always at least one subgame perfect equilibrium...