This dissertation contains three essays on choice and voting theory. In Chapter

1, a model of stochastic choice is proposed and characterized. Randomness in

choice is driven by variability in the availability of alternatives. Chapter 2 addresses

the classic implementation problem in a spatial setting. A social choice rule is

recommended that can be viewed as a spatial analogue to majority rule as originally

axiomatized by May (1952). Chapter 3 investigates testability, identification, and

estimation in a large class of models used in modeling voting behavior. The models

have relevance to the growing number of online voting platforms.