This paper provides first and second-order approximation methods for the solution of non-linear dynamic stochastic models in which the exogenous state variables follow conditionally-linear stochastic processes displaying time-varying risk. The first-order approximation is consistent with a...

"Fixed-Up-To" (FUT) tariffs, which are commonly used for pricing telecommunication services, are made up of three parts: a monthly subscription fee (or fixed fee), a usage-limit (or allowance), and an over-limit rate that is used for pricing consumptions in excess of the usage-limit. Typically,...