CST_Calibration.Rd

% Generated by roxygen2: do not edit by hand
% Please edit documentation in R/CST_Calibration.R
\name{CST_Calibration}
\alias{CST_Calibration}
\title{Forecast Calibration}
\usage{
CST_Calibration(
  exp,
  obs,
  exp_cor = NULL,
  cal.method = "mse_min",
  eval.method = "leave-one-out",
  multi.model = FALSE,
  na.fill = TRUE,
  na.rm = TRUE,
  apply_to = NULL,
  alpha = NULL,
  memb_dim = "member",
  sdate_dim = "sdate",
  ncores = 1
)
}
\arguments{
\item{exp}{an object of class \code{s2dv_cube} as returned by \code{CST_Load} function, containing the seasonal hindcast experiment data in the element named \code{$data}. The hindcast is used to calibrate the forecast in case the forecast is provided; if not, the same hindcast will be calibrated instead.}

\item{obs}{an object of class \code{s2dv_cube} as returned by \code{CST_Load} function, containing the observed data in the element named \code{$data}.}

\item{exp_cor}{an optional object of class \code{s2dv_cube} as returned by \code{CST_Load} function, containing the seasonal forecast experiment data in the element named \code{$data}. If the forecast is provided, it will be calibrated using the hindcast and observations; if not, the hindcast will be calibrated instead.}

\item{cal.method}{is the calibration method used, can be either \code{bias}, \code{evmos}, \code{mse_min}, \code{crps_min} or \code{rpc-based}. Default value is \code{mse_min}.}

\item{eval.method}{is the sampling method used, can be either \code{in-sample} or \code{leave-one-out}. Default value is the \code{leave-one-out} cross validation. In case the forecast is provided, any chosen eval.method is over-ruled and a third option is used.}

\item{multi.model}{is a boolean that is used only for the \code{mse_min} method. If multi-model ensembles or ensembles of different sizes are used, it must be set to \code{TRUE}. By default it is \code{FALSE}. Differences between the two approaches are generally small but may become large when using small ensemble sizes. Using multi.model when the calibration method is \code{bias}, \code{evmos} or \code{crps_min} will not affect the result.}

\item{na.fill}{is a boolean that indicates what happens in case calibration is not possible or will yield unreliable results. This happens when three or less forecasts-observation pairs are available to perform the training phase of the calibration. By default \code{na.fill} is set to true such that NA values will be returned. If \code{na.fill} is set to false, the uncorrected data will be returned.}

\item{na.rm}{is a boolean that indicates whether to remove the NA values or not. The default value is \code{TRUE}. See Details section for further information about its use and compatibility with \code{na.fill}.}

\item{apply_to}{is a character string that indicates whether to apply the calibration to all the forecast (\code{"all"}) or only to those where the correlation between the ensemble mean and the observations is statistically significant (\code{"sign"}). Only useful if \code{cal.method == "rpc-based"}.}

\item{alpha}{is a numeric value indicating the significance level for the correlation test. Only useful if \code{cal.method == "rpc-based" & apply_to == "sign"}.}

\item{memb_dim}{is a character string indicating the name of the member dimension. By default, it is set to 'member'.}

\item{sdate_dim}{is a character string indicating the name of the start date dimension. By default, it is set to 'sdate'.}

\item{ncores}{is an integer that indicates the number of cores for parallel computations using multiApply function. The default value is one.}
}
\value{
an object of class \code{s2dv_cube} containing the calibrated forecasts in the element \code{$data} with the same dimensions as the one in the exp object.
}
\description{
Equivalent to function \code{Calibration} but for objects of class \code{s2dv_cube}.
}
\examples{
# Example 1:
mod1 <- 1 : (1 * 3 * 4 * 5 * 6 * 7)
dim(mod1) <- c(dataset = 1, member = 3, sdate = 4, ftime = 5, lat = 6, lon = 7)
obs1 <- 1 : (1 * 1 * 4 * 5 * 6 * 7)
dim(obs1) <- c(dataset = 1, member = 1, sdate = 4, ftime = 5, lat = 6, lon = 7)
lon <- seq(0, 30, 5)
lat <- seq(0, 25, 5)
exp <- list(data = mod1, lat = lat, lon = lon)
obs <- list(data = obs1, lat = lat, lon = lon)
attr(exp, 'class') <- 's2dv_cube'
attr(obs, 'class') <- 's2dv_cube'
a <- CST_Calibration(exp = exp, obs = obs, cal.method = "mse_min", eval.method = "in-sample")
str(a)

# Example 2:
mod1 <- 1 : (1 * 3 * 4 * 5 * 6 * 7)
mod2 <- 1 : (1 * 3 * 1 * 5 * 6 * 7)
dim(mod1) <- c(dataset = 1, member = 3, sdate = 4, ftime = 5, lat = 6, lon = 7)
dim(mod2) <- c(dataset = 1, member = 3, sdate = 1, ftime = 5, lat = 6, lon = 7)
obs1 <- 1 : (1 * 1 * 4 * 5 * 6 * 7)
dim(obs1) <- c(dataset = 1, member = 1, sdate = 4, ftime = 5, lat = 6, lon = 7)
lon <- seq(0, 30, 5)
lat <- seq(0, 25, 5)
exp <- list(data = mod1, lat = lat, lon = lon)
obs <- list(data = obs1, lat = lat, lon = lon)
exp_cor <- list(data = mod2, lat = lat, lon = lon)
attr(exp, 'class') <- 's2dv_cube'
attr(obs, 'class') <- 's2dv_cube'
attr(exp_cor, 'class') <- 's2dv_cube'
a <- CST_Calibration(exp = exp, obs = obs, exp_cor = exp_cor, cal.method = "evmos")
str(a)
}
\seealso{
\code{\link{CST_Load}}
}
\author{
Verónica Torralba, \email{veronica.torralba@bsc.es}

Bert Van Schaeybroeck, \email{bertvs@meteo.be}
}