Resumen
The system differential response method for inverse estimation has received much attention in the hydrology literature. However, its underlying mechanisms remain largely unexplored, highlighting the need for this study. This study proposes the relation degree coefficient (RC) concept describing the nonlinear relationships between different variables and demonstrates that the selective information extraction ability of the method was first demonstrated from a theoretical perspective. Synthetic cases were conducted to demonstrate the method performance under various variables to be estimated. The results show that the useful information is extracted from the relationship between the variables to be estimated and the observed discharge. In addition, there is a general trend that suggests that incorporating more variables into the inversion estimation can lead to enhanced estimation performance.