Random forests via ranger::ranger(). Binary targets use a probability
forest and fractional pseudo-labels a regression forest, so soft final-fit
targets are supported natively. The backend performs no internal
cross-validation; its hyperparameters are fixed at construction.
Out-of-bag predictions supply fit_predict, so the stored predictions and
classification cutoff use honest scores rather than in-sample memorization.
Usage
xplus_backend_ranger(
trees = 500,
mtry = NULL,
min_n = 1,
max.depth = 0,
num.threads = 1,
seed = NULL,
importance.mode = c("impurity", "permutation", "none")
)Arguments
- trees
Number of trees (ranger
num.trees); the parsnip-harmonized name is used so a parsnip bridge can maprand_forest(trees = ...)later.- mtry
Number of variables sampled per split;
NULLuses the ranger default.- min_n
Minimum node size (ranger
min.node.size).- max.depth, num.threads
Engine-specific ranger controls forwarded unchanged.
- seed
Optional seed passed to each ranger fit. When
NULL, one is drawn from R's RNG per fit so thatxplus(seed = ...)remains reproducible.- importance.mode
Variable-importance mode (
"impurity","permutation", or"none").
Examples
if (FALSE) { # \dontrun{
fit <- xplus(x, y, backend = xplus_backend_ranger(trees = 1000))
} # }