#'Find a weighted climate window
#'
#'Finds the best weighted average of a weather variable over a period that
#'correlates most strongly with a biological variable. Uses weibull or
#'Generalised Extreme Value (GEV) distribution. See references for a full
#'description.
#'
#'@param n The number of iterations used to run weightwin. If n > 1, iterations
#'will use randomly generated starting parameters. These are stored in the
#'output data frame `iterations`.
#'@param xvar A list object containing all climate variables of interest.
#' Please specify the parent environment and variable name (e.g. Climate$Temp).
#'@param cdate The climate date variable. Please specify the parent environment
#' and variable name (e.g. Climate$Date).
#'@param bdate The biological date variable. Please specify the parent
#' environment and variable name (e.g. Biol$Date).
#'@param baseline The baseline model structure used for testing correlation.
#' Currently known to support lm, lme, glm and glmer objects.
#'@param range Two values signifying respectively the furthest and closest number
#' of time intervals (set by cinterval) back from the cutoff date or biological record to include
#' in the climate window search.
#'@param func The function used to fit the climate variable in the model. Can be
#' linear ("lin"), quadratic ("quad"), cubic ("cub"), inverse ("inv") or log ("log").
#'@param type "absolute" or "relative", whether you wish the climate window to be relative
#' (e.g. the number of days before each biological record is measured) or absolute
#' (e.g. number of days before a set point in time).
#'@param refday If type is absolute, the day and month respectively of the
#' year from which the absolute window analysis will start.
#'@param cmissing Determines what should be done if there are
#' missing climate data. Three approaches are possible:
#' - FALSE; the function will not run if missing climate data is encountered.
#' An object 'missing' will be returned containing the dates of missing climate.
#' - "method1"; missing climate data will be replaced with the mean climate
#' of the preceding and following 2 records.
#' - "method2"; missing climate data will be replaced with the mean climate
#' of all records on the same date.
#'
#' Note: Other methods are possible. Users should consider those methods most
#' appropriate for their data and apply them manually before using climwin if
#' required.
#'@param cohort A variable used to group biological records that occur in the same biological
#' season but cover multiple years (e.g. southern hemisphere breeding season). Only required
#' when type is "absolute". The cohort variable should be in the same dataset as the variable bdate.
#'@param weightfunc The distribution to be used for optimisation. Can be
#' either a Weibull ("W") or Generalised Extreme Value distribution ("G").
#'@param cinterval The resolution at which the climate window analysis will be
#' conducted. May be days ("day"), weeks ("week"), or months ("month"). Note the units
#' of parameter 'range' will differ depending on the choice
#' of cinterval.
#'@param k The number of folds used for k-fold cross validation. By default
#' this value is set to 0, so no cross validation occurs. Value should be a
#' minimum of 2 for cross validation to occur.
#'@param spatial A list item containing:
#' 1. A factor that defines which spatial group (i.e. population) each biological
#' record is taken from. The length of this factor should correspond to the length
#' of the biological dataset.
#' 2. A factor that defines which spatial group (i.e. population) climate data
#' corresponds to. This length of this factor should correspond to the length of
#' the climate dataset.
#'@param par Shape, scale and location parameters of the Weibull or GEV weight
#' function used as start weight function. For Weibull : Shape and scale
#' parameters must be greater than 0, while location parameter must be less
#' than or equal to 0. For GEV : Scale parameter must be greater than 0.
#'@param control Parameters used to determine step size for the optimisation
#' function. Please see \code{\link{optim}} for more detail.
#'@param method The method used for the optimisation function. Please see
#' \code{\link{optim}} for more detail.
#'@param cutoff.day,cutoff.month Redundant parameters. Now replaced by refday.
#'@param furthest,closest Redundant parameters. Now replaced by range.
#'@param nrandom Used when conducting data randomisation, should not be
#' changed manually.
#'@param centre A list item containing:
#' 1. The variable used for mean centring (e.g. Year, Site, Individual).
#' Please specify the parent environment and variable name (e.g. Biol$Year).
#' 2. Whether the model should include both within-group means and variance ("both"),
#' only within-group means ("mean"), or only within-group variance ("var").
#'@param grad Run the optimisation procedure with a numerically derived gradient function.
#' This can improve model convergence but will increase computational time.
#'@references van de Pol & Cockburn 2011 Am Nat 177(5):698-707 (doi:
#' 10.1086/659101) "Identifying the critical climatic time window that affects
#' trait expression"
#'@return Produces a constantly updating grid of plots as the optimisation
#' function is running.
#' \itemize{
#' \item Right panel from top to bottom: The
#' three parameters (shape, scale and location) determining the weight
#' function.
#'
#' \item Left top panel: The resulting weight function.
#'
#' \item Left middle panel: The delta AICc compared to the baseline model.
#'
#' \item Left bottom panel: Plotted relationship between the weighted mean of climate
#' and the biological response variable.}
#'
#' Also returns a list containing three objects: \itemize{
#' \item BestModel, a model object. The best weighted window model determined
#' by deltaAICc.
#'
#' \item BestModelData, a dataframe. Biological and climate data used to fit
#' the best weighted window model.
#'
#' \item WeightedOutput. Parameter values for the best weighted window.
#'
#' \item iterations. If n > 1, the starting parameters and deltaAICc values
#' from each iteration of weightwin.
#' }
#'@author Martijn van de Pol and Liam D. Bailey
#'@examples
#'
#'#Simple test example
#'#Create data from a subset of our test dataset
#'biol_data <- Mass[1:5, ]
#'data(MassClimate)
#'
#'
#'weight <- weightwin(xvar = list(Temp = MassClimate$Temp),
#' cdate = MassClimate$Date,
#' bdate = biol_data$Date,
#' baseline = glm(Mass ~ 1, data = biol_data),
#' range = c(100, 0), func = "lin",
#' type = "relative", weightfunc = "W", cinterval = "day",
#' par = c(2.26, 8.45, 0), control = list(ndeps = c(0.01, 0.01, 0.01)),
#' method = "L-BFGS-B")
#'
#'
#'\dontrun{
#'
#'# Full working example
#'
#'# Test for a weighted average over a fixed climate window
#'# using datasets 'Offspring' and 'OffspringClimate'
#'
#'# N.B. THIS EXAMPLE MAY TAKE A MOMENT TO CONVERGE ON THE BEST MODEL.
#'
#'# Load data
#'
#'data(Offspring)
#'data(OffspringClimate)
#'
#'# Test for climate windows between 365 and 0 days ago (range = c(365, 0))
#'# Fit a quadratic term for the mean weighted climate (func="quad")
#'# in a Poisson regression (offspring number ranges 0-3)
#'# Test a variable window (type = "absolute")
#'# Test at the resolution of days (cinterval="day")
#'# Uses a Weibull weight function (weightfunc="week")
#'
#'weight <- weightwin(xvar = list(Temp = OffspringClimate$Temperature),
#' cdate = OffspringClimate$Date,
#' bdate = Offspring$Date,
#' baseline = glm(Offspring ~ 1, family = poisson, data = Offspring),
#' range = c(365, 0), func = "quad",
#' type = "relative", weightfunc = "W", cinterval = "day",
#' par = c(3, 0.2, 0), control = list(ndeps = c(0.01, 0.01, 0.01)),
#' method = "L-BFGS-B")
#'
#'# View output
#'
#'head(weight[[3]])
#'summary(weight[[1]])
#'head(weight[[2]])
#' }
#'
#'@importFrom evd dgev
#'@import numDeriv
#'@export
weightwin <- function(n = 1, xvar, cdate, bdate, baseline, range, k = 0,
func = "lin", type, refday, nrandom = 0, centre = NULL,
weightfunc = "W", cinterval = "day", cmissing = FALSE, cohort = NULL, spatial = NULL,
par = c(3, 0.2, 0), control = list(ndeps = c(0.001, 0.001, 0.001)),
method = "L-BFGS-B", cutoff.day = NULL, cutoff.month = NULL,
furthest = NULL, closest = NULL, grad = FALSE){
if(n == 1){
single_weight <- suppressMessages(basewin_weight(n = n, xvar = xvar, cdate = cdate, bdate = bdate,
baseline = baseline, range = range, func = func,
type = type, refday = refday, nrandom = nrandom,
centre = centre, weightfunc = weightfunc, k = k,
cinterval = cinterval, cmissing = cmissing, cohort = cohort,
spatial = spatial, par = par, control = control,
method = method, cutoff.day = cutoff.day, cutoff.month = cutoff.month,
furthest = furthest, closest = closest, grad = grad))
return(single_weight)
} else {
weight.list <- list()
par.list <- list()
pb <- txtProgressBar(min = 0, max = n, style = 3, char = "|")
for(i in 1:n){
if(weightfunc == "W"){
if(i == 1){
par = par
save_par <- data.frame(start_shape = par[1], start_scale = par[2], start_location = par[3])
} else {
par = c(runif(1, min = 0.1, max = 10), runif(1, min = 0.1, max = 10), runif(1, min = -10, max = 0))
save_par <- data.frame(start_shape = par[1], start_scale = par[2], start_location = par[3])
}
} else if(weightfunc == "G"){
if(i == 1){
par = par
save_par <- data.frame(start_shape = par[1], start_scale = par[2], start_location = par[3])
} else {
par = c(runif(1, min = -10, max = 10), runif(1, min = 0.1, max = 10), runif(1, min = -10, max = 10))
save_par <- data.frame(start_shape = par[1], start_scale = par[2], start_location = par[3])
}
} else if(weightfunc == "U"){
if(i == 1){
par = par
save_par <- data.frame(start_open = par[1], start_close = par[2])
} else {
open = runif(1, min = range[2], max = range[1])
close = runif(1, min = range[2], max = open)
par = c(open, close)
save_par <- data.frame(start_open = par[1], start_close = par[2])
}
}
weight.list[[i]] <- suppressMessages(basewin_weight(n = n, xvar = xvar, cdate = cdate, bdate = bdate, k = k,
baseline = baseline, range = range, func = func,
type = type, refday = refday, nrandom = nrandom,
centre = centre, weightfunc = weightfunc,
cinterval = cinterval, cmissing = cmissing, cohort = cohort,
spatial = spatial, par = par, control = control,
method = method, cutoff.day = cutoff.day, cutoff.month = cutoff.month,
furthest = furthest, closest = closest, grad = grad))
weight.list[[i]]$WeightedOutput <- merge(save_par, weight.list[[i]]$WeightedOutput)
par.list[[i]] <- merge(save_par, data.frame(deltaAICc = weight.list[[i]]$WeightedOutput$deltaAICc))
setTxtProgressBar(pb, i - 1)
}
setTxtProgressBar(pb, n)
print(do.call(rbind, par.list))
weight.list$iterations <- do.call(rbind, par.list)
return(weight.list)
}
}
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