tac.is: TAC implementation system module

In flr/mse: Tools for Running Management Strategy Evaluations using FLR

TAC implementation system module

Description

Performs a short term forecast (STF) for the target fishing mortality to obtain the corresponding catch.

Usage

tac.is(
  stk,
  ctrl,
  args,
  output = "catch",
  recyrs = -2,
  Fdevs = fbar(fut) %=% 1,
  dtaclow = NA,
  dtacupp = NA,
  fmin = 0,
  reuse = TRUE,
  initac = metrics(stk, output)[, ac(iy - 1)],
  tracking
)

Arguments

stk	The perceived FLStock.
ctrl	The fwdControl output by the hcr step, target must be 'fbar'.
args	The MSE run arguments.
recyrs	Years to use for geometric mean recruitment if projection. Defaults to all years minus the last two.
Fdevs	Deviances on the fbar input to incorporate error and bias when MP is run using the pseudo-estimators 'perfect.sa' or 'shortcut.sa'.
dtaclow	Limit to decreases in output catch, as a proportional change (0.85 for 15%). Applied only when metric > lim, as set by 'hcr' step.
dtacupp	Limit to increases in output catch, as a proportional change (1.15 for 15%). Applied only when metric > lim, as set by 'hcr' step.
fmin	Minimum fbar to apply when catch change limits are use.
initac	Initial catch from which to compute catch change limits. Defaults to previous observed catch.
tracking	The tracking object.

Details

A fwdControl object obtained from the 'hcr' step is applied in the management year (ay + mlag) or years (⁠seq(ay + mlag, ay + mlag + freq⁠). An assumption is made on the mortality in the assessment year (ay), which becomes the intermediate year in this projection. By default this is set to Fbar = Fsq, that is, the same fishing mortality estimated in the last data year (ay - data_lag).

The projection applies a constant recruitment, equal to the geometric mean over an specified number of years. By default all years minus the last two are included in the calculation. An specific set of years can be employed, by specifying a character vector of year names, or two values can be given for the number of years to be inlcuded, counting from the last, and how many years to exclude at the end. For example, c(30, 2) will use the last 30 years but excluding the last two, usually worst estimated.

Examples

data(sol274)
# Setup control with tac.is
control <- mpCtrl(list(est=mseCtrl(method=perfect.sa),
  hcr=mseCtrl(method=hockeystick.hcr,
    args=list(lim=0, trigger=4.3e5, target=0.21)),
  isys=mseCtrl(method=tac.is, args=list(recyrs=-3, output='landings'))))
# Run MP until 2025
run <- mp(om, oem, ctrl=control, args=list(iy=2021, fy=2027))
# Plot run time series
plot(om, TAC.IS=run)

flr/mse documentation built on Dec. 18, 2024, 10:38 p.m.