In this new publication, regional regression models using a set of three variables (mean annual precipitation, potential evapotranspiration, and baseflow index) selected via expert assessment was found to be effective in predicting percentile flows and performed similarly to larger sets of variables selected using a data-driven method.

Fouad, G.,  Skupin, A., Tague, C.L. (2018) Regional regression models of percentile flows for the contiguous United States: Expert versus data-driven independent variable selection, Journal of Hydrology: Regional Studies 17:64-82,