This paper provides an overview of some alternative conceptual definitions of travel time variability, discusses their implications about behaviour, and puts them into a broader context, including deviations from the underlying assumptions regarding rational behaviour. The paper then discusses...

We consider demand systems for utility-maximizing consumers facing general budget constraints whose utilities are perturbed by additive linear shifts in marginal utilities. Budgets are required to be compact but are not required to be convex. We define demand generating functions (DGF) whose...