R: Robust Boosting Path for Truncated Loss Functions
rbstpath
R Documentation
Robust Boosting Path for Truncated Loss Functions
Description
Gradient boosting path for optimizing robust loss functions with componentwise
linear, smoothing splines, tree models as base learners.
Usage
rbstpath(x, y, rmstop=seq(40, 400, by=20), ctrl=bst_control(), del=1e-16, ...)
Arguments
x
a data frame containing the variables in the model.
y
vector of responses. y must be in {1, -1}.
rmstop
vector of boosting iterations
ctrl
an object of class bst_control.
del
convergency critera
...
arguments passed to rbst
Details
This function invokes rbst with mstop being each element of vector rmstop. It can provide different paths. Thus rmstop serves as another hyper-parameter. However, the most important hyper-parameter is the loss truncation point.
Value
A length rmstop vector of lists with each element being an object of class rbst.
Author(s)
Zhu Wang
See Also
rbst
Examples
x <- matrix(rnorm(100*5),ncol=5)
c <- 2*x[,1]
p <- exp(c)/(exp(c)+exp(-c))
y <- rbinom(100,1,p)
y[y != 1] <- -1
y[1:10] <- -y[1:10]
x <- as.data.frame(x)
dat.m <- bst(x, y, ctrl = bst_control(mstop=50), family = "hinge", learner = "ls")
predict(dat.m)
dat.m1 <- bst(x, y, ctrl = bst_control(twinboost=TRUE,
coefir=coef(dat.m), xselect.init = dat.m$xselect, mstop=50))
dat.m2 <- rbst(x, y, ctrl = bst_control(mstop=50, s=0, trace=TRUE),
rfamily = "thinge", learner = "ls")
predict(dat.m2)
rmstop <- seq(10, 40, by=10)
dat.m3 <- rbstpath(x, y, rmstop, rfamily = "thinge", learner = "ls")