cf_downscale            Coarse-to-fine spatial downscaling (CF-DS)
cf_downscale_hv         Holdout validation for the coarse-to-fine
                        spatial downscaling (CF-DS)
cf_glm                  Coarse-to-fine spatial generalized linear mixed
                        models (CF-GLMMs)
cf_glm_hv               Holdout validation for coarse-to-fine spatial
                        generalized linear mixed models (CF-GLMMs)
cf_lm                   Coarse-to-fine spatial modeling (CFSM) for
                        Gaussian response
cf_lm_hv                Holdout validation for the Gaussian
                        coarse-to-fine spatial modeling (CFSM)
sp_scalewise            Extract scale-wise spatial processes
