Curve Fitting and Regression Analysis

Abstract

Curve fitting and regression analysis are powerful statistical tools used widely in hydrological data modeling. They can be used to model underlying relationships between data, allowing you to interpret and predict hydrological behavior under varying conditions. Curve fitting involves fitting a function on a set of data points that best represents the underlying trend in the dataset. Curve fitting supports essential tasks such as deriving intensity-duration-frequency (IDF) curves for rainfall, which describe the occurrence frequency, duration, and intensity of a rain event. These curves are critical for managing flood risk and designing effective dams, reservoirs, or drainage systems. Likewise, they also help in modeling hydrographs, a way to depict the water flow rate over time, and anticipating and managing river discharge patterns. Regression analysis, a form of curve fitting, is often used to model the relationship between two or more variables. This technique determines the equation that best describes the dependent variable in terms of the independent variables. Rainfall-runoff modeling can use regression analysis to establish the relationship between streamflow (dependent variable) and rainfall (independent variable). This relationship is vital for water resource management, water availability, and forecasting of floods.