R/ICcforest-package.R

In ICcforest: An Ensemble Method for Interval-Censored Survival Data

#' Construct a conditional inference forest model for interval-censored survival data
#' 
#' Construct a conditional inference forest model for interval-censored survival data.
#' The main function of this package is \code{\link{ICcforest}}.
#' 
#' \subsection{Problem setup and existing methods}{
#' In many situations, the survival time cannot be directly observed and it is only 
#' known to have occurred in an interval obtained from a sequence of examination times. 
#' Methods like the Cox proportional hazards model rely on restrictive assumptions such as 
#' proportional hazards and a log-linear relationship between the hazard function and 
#' covariates. Furthermore, because these methods are often parametric, nonlinear effects 
#' of variables must be modeled by transformations or expanding the design matrix to 
#' include specialized basis functions for more complex data structures in real world 
#' applications. The function \code{\link[LTRCtrees]{ICtree}} in the \code{LTRCtrees}
#' package provides a conditional inference tree method for interval-censored survival data, 
#' as an extension of the conditional inference tree method \code{\link[partykit]{ctree}}
#' for right-censored data. Tree estimators are nonparametric and as such often exhibit 
#' low bias and high variance. Ensemble methods like bagging and random forest can 
#' reduce variance while preserving low bias.}
#' 
#' \subsection{ICcforest model}{
#' This package implements \code{\link{ICcforest}}, which extends the conditional inference forest 
#' (see \code{\link[partykit]{cforest}}) to interval censored data. \code{\link{ICcforest}} uses 
#' conditional inference survival trees (see \code{\link[LTRCtrees]{ICtree}}) as base learners. 
#' The main function \code{\link{ICcforest}} fits a 
#' conditional inference forest for interval-censored survival data, with parameter 
#' \code{mtry} tuned by \code{\link{tuneICRF}}; \code{\link{gettree.ICcforest}} extracts 
#' the i-th individual tree from the established \code{ICcforest} objects; and 
#' \code{\link{predict.ICcforest}} computes predictions from \code{ICcforest} objects.}
#' 
#' @seealso \code{\link{ICcforest}, \link{gettree.ICcforest}, \link{predict.ICcforest},  
#' \link{tuneICRF}, \link{sbrier_IC}}
#' @docType package
#' @keywords package
#' @name ICcforest-package
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