1. A predictive system for predicting operation of a plant or process, comprising: a non-linear model comprising: an empirical representation of the plant or process; a first input operable to receive an input value; and a first output operable to provide a first output value; wherein the non-linear model is operable to receive the input value and generate the first output value using the empirical representation of the plant or process; a linearized first principles model comprising: an analytic representation of the plant or process, wherein the analytic representation of the plant or process is independent of the empirical representation; a second input operable to receive the input value; and a second output operable to provide a second output value; wherein the linearized first principles model is operable to receive the input value and generate the second output value using the analytic representation of the plant or process; a domain analyzer operable to determine whether the input value falls within a region of space where the non-linear model has an integrity that is less than a first threshold; and a controller operable to: use the non-linear model when the integrity is above the first threshold; and use the linearized first principles model when the integrity is below the first threshold; wherein the first output value and/or the second output value is usable to manage the plant or process.