dr_rulsif {S4DM} | R Documentation |
Density-ratio SDM estimation with RuLSIF
Description
dr_rulsif is an internal function for density-ratio estimation with RuLSIF (Kanamori et al. 2009; Yamada et al. 2013).
Usage
dr_rulsif(
presence_data = NULL,
background_data = NULL,
projection_data = NULL,
sigma = 10^seq(-3, 1, length.out = 9),
lambda = 10^seq(-3, 1, length.out = 9),
alpha = 0.1,
kernel_num = 100,
verbose = FALSE,
method,
object = NULL
)
Arguments
presence_data |
dataframe of covariates |
background_data |
dataframe of covariates |
projection_data |
dataframe of covariates |
sigma |
Sigma parameter for RuLSIF. Default is the RuLSIF default. |
lambda |
Lambda parameter for RuLSIF. Default is the RuLSIF default. |
alpha |
Relative parameter. Defaults to RuLSIF default. |
kernel_num |
kernel_number for RuLSIF. Default is the RuLSIF default. |
method |
one of either "fit" or "predict" |
object |
fitted object returned by a dr_... function. Only needed when method = "predict" |
References
Kanamori T, Hido S, Sugiyama M (2009).
“A least-squares approach to direct importance estimation.”
J. Mach. Learn. Res., 10, 1391–1445.
https://www.jmlr.org/papers/volume10/kanamori09a/kanamori09a.pdf.
Yamada M, Suzuki T, Kanamori T, Hachiya H, Sugiyama M (2013).
“Relative Density-Ratio Estimation for Robust Distribution Comparison.”
Neural Computation, 25(5), 1324–1370.
http://dx.doi.org/10.1162/neco_a_00442.