Estimation of parameters for the Philip two-term infiltration equation applied to field soil experiments

Abstract

Two methods based on least squares analysis used to estimate coefficients in the Philip two-term infiltration equation are compared. The one method maintains the infiltration equation in its original form, while the other involves a mathematical transformation which introduces self-correlation and yields different estimates of the coefficients. Data from field infiltration experiments are used to illustrate these differences, and the need to distinguish between fitting data to empirical models and deriving system parameters from analysis of physically based models is emphasized.