1. A computer-implemented method for valuating a security, said method comprising the steps of: selecting a model equation, stored in an electronic storage medium on a computer, for modeling the relation of one or more derived variables and one or more state variables; receiving one or more parameters related to the selected model equation, wherein the one or more parameters includes current data, historical data, security-specific data or general market data stored in an electronic storage medium on a computer, and wherein the use of data received as a parameter is dictated by the model equation selected by the computer configured to process the one or more parameters; generating one or more Monte Carlo paths for the one or more state variables based on the one or more parameters related to the selected model equation; generating a lattice for the one or more state variables; calculating, by the computer, values of the at least one derived variable on the lattice; calculating, by the computer, values of the at least one derived variable on the Monte Carlo path based on the values of the at least one derived variable on the lattice; and providing a valuation for the security based on the at least one derived variable.