The authors study the relationship that exists between two families of models of product differentiation: the class of location or Hotelling-type models of horizontal differentiation, and models of vertical differentiation. Their main result is that every model belonging to a very large class of...

The authors introduce commodity taxation into a vertical differentiation model with endogenous product selection. They show that a uniform ad valorem tax lowers both qualities, distorts the allocation of consumers between firms, and lowers the consumer prices of both variants. A small uniform...