Compute a retrospective hindcast cross-validation of a4a stock and indices

The output of a4ahcxval consist of a list with two elements, named 'stocks' and 'indices'. The first is an object of class FLStocks, each a peel from the restrospective run. The second element is a list of FLIndices object. The first FLIndices object, named 'data', is a copy of the input 'indices' argument, with the additoned catch.n slot, if originally missing. The next element, named as the final year of the data set, contains the naive prediction of the input FLIndices, while the remaining elements are the result of a hindcast prediction of the relevant indices, those within the year range of as set ny nyears.

a4ahcxval(stock, indices, nyears = 5, nsq = 3, check.ks = FALSE, ...)

Arguments

stock

Input FLStock object.

indices

Input FLIndices object.

nyears

Number if years for retrospective, defaults to 5.

nsq

Number of years for average biology and selectivity, defaults to 3.

...

Any submodels and other arguments for the call to sca.

fixed.ks

Is the number of knots is splines with 'year' constant?

Value

A list containing elements 'stocks', of class FLStocks, and 'indices', a list of FLIndices objects. See details for structure of this list.

Examples

data(sol274)
 # models
fmod <- ~te(replace(age, age > 8, 8), year, k = c(4, 22)) +
  s(replace(age, age > 8, 8), k=4) +
  s(year, k=22, by=as.numeric(age==1))
qmod <- list(~s(age, k=3), ~s(age, k=3))
vmod <- list(~s(age, k=3), ~s(age, k=3), ~s(age, k=3))
srmod <- ~factor(year)
# RUN xval
xval <- a4ahcxval(stock, indices, fmodel=fmod, qmodel=qmod, vmodel=vmod)
#> Warning: executing %dopar% sequentially: no parallel backend registered
# PLOT result
plotXval(xval$indices)