ABSTRACT
For analysis and planning purposes of watersheds, simulation of hydrologic events is needed. Hydrologic simulation models are used to provide a hydrologic prediction/projection as well as better understanding of processes within the hydrologic cycle. A variety of modeling approaches are used for this purpose. These models are a simplified conceptual representation of a part/component of the global water cycle. Different classifications are considered for hydrologic simulation. Two groups of hydrologic models are often defined:
1. Data-driven mathematical models: In these models, mathematical and statistical concepts are used to develop a relationship between model input(s) such as rainfall and temperature and model output such as runoff. The common procedures used in these models are regression, transfer functions, neural networks, fuzzy inference, and system identification. These models can be deterministic or stochastic.
