Functions which make using the Generalized Regression Estimator(GREG)
J.N.K. Rao, Isabel Molina, (2015) <10.3390>
and the Generalized Regression Estimator Operating on Resolutions of Y (GREGORY) easier.
The functions are designed to work well within a forestry context, and estimate multiple
estimation units at once. Compared to other survey estimation packages, this function has greater flexibility when
describing the linear model.10.3390>