An abstract construct to represent a system for the purposes of reproducing, simplifying, analyzing, or understanding it. The definition of a Model can be broadly divided into perceptual, conceptual and procedural models. (see Beven, 2001)

• Model, Perceptual - Summary of our (personal) perceptions on how a system responds. Perceptual nodels are frameworks representing how a given theorist views the phenomena of concern to a discipline. People receive information, process this information, and respond accordingly many times each day. This sort of processing of information is essentially a perceptual

• Model of how things in our surrounding environment work. The perceptual understanding of systems is far greater than most material model implementations. (see Beven, 2001)

• Model, Conceptual - The mathematical description of a perceptual model is a conceptual model. It is a construct of mathematical and logical statements that describe a complex system in quantitative terms; a carefully constructed, but sharply limited simulation of nature. It includes hypotheses and assumptions to simplify the processes. (see Beven, 2001)

• Model, Procedural - Converts a conceptual model essentially to a computer code for example the replacement of differentials of the original equation by finite-difference or finite-volume equivalents. (see Beven, 2001)

References

Beven, K.J., 2001. Rainfall-Runoff Modelling: The Primer. Wiley, New York.