reduce {gecko} | R Documentation |
Reduce dimensionality of raster layers.
Description
Reduce the number of layers by either performing a PCA on them or by eliminating highly correlated ones.
Usage
reduce(layers, method = "pca", n = NULL, thres = NULL)
Arguments
layers |
SpatRaster. As defined in package terra, see |
method |
character. Either Principal Components Analysis ("pca", default) or Pearson's correlation ("cor"). |
n |
numeric. Number of layers to reduce to. |
thres |
numeric. Value for pairwise Pearson's correlation above which one of the layers (randomly selected) is eliminated. |
Details
Using a large number of explanatory variables in models with few records may lead to overfitting. This function allows to avoid it as much as possible. If both n and thres are given, n has priority. If method is not recognized and layers come from read function, only landcover is reduced by using only the dominating landuse of each cell.
Value
SpatRaster.