CVEK: Cross-Validated Kernel Ensemble

#' Dataset as an example
#'
#' A dataset containing a response variable and four predictor variables. 
#' The variables are as follows:
#'
#' \itemize{
#'   \item y. (vector of length n) Reponses of the dataframe.
#'   \item x1. (dataframe, n*1) The first variable in the dataframe.
#'   \item x2. (dataframe, n*1) The second variable in the dataframe.
#'   \item x3. (dataframe, n*1) The third variable in the dataframe.
#'   \item x4. (dataframe, n*1) The fourth variable in the dataframe.
#' }
#'
#' @docType data
#' @keywords datasets
#' @name dora
#' @usage data(dora)
#' @format A data frame with 100 rows and 5 variables
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