projection: Projections for assessment models

View source: R/define_S4_class_project.R

projectionR Documentation

Projections for assessment models

Description

This function takes an assessment model and runs a stochastic projection based on future F or catch.

Usage

projection(
  Assessment,
  constrain = c("F", "Catch"),
  Ftarget,
  Catch,
  p_years = 50,
  p_sim = 200,
  obs_error,
  process_error,
  max_F = 3,
  seed = 499
)

Arguments

Assessment

An object of class Assessment.

constrain

Whether to project on future F or catch. By default, projects on F.

Ftarget

The projection F, either of length 1 for constant F for the entirety of the projection or length p_years.

Catch

The projection catch, either of length 1 for constant catch for the entirety of the projection or length p_years.

p_years

Integer for the number of projection years.

p_sim

Integer for the number of simulations for the projection.

obs_error

A list of length two. In the first entry, a vector of length nsurvey giving the standard deviations of each future index, or alternatively an array of dimension p_sim, p_years, and nsurvey giving the deviates. The second entry is the standard deviation of the projected catch. Alternatively, a matrix of simulation and year-specific error structure for the catch (p_sim rows and p_year columns; a matrix of ones indicates perfect data).

process_error

Numeric, standard deviation for process error (e.g., recruitment or biomass deviates). If NULL, uses values from assessment model. Alternatively, a matrix of simulation and year-specific recruitment deviates (p_sim rows and p_year columns, a matrix of ones indicates no recruitment deviates).

max_F

The maximum allowable F if the projection is constrained on catch.

seed

An integer to set the seed for the sampling observation and process error deviates.

Value

An object of class project that contains future predicted values of F, catch, biomass, recruitment, etc.

Examples


myAssess <- SP(Data = swordfish)
do_projection <- projection(myAssess, Ftarget = myAssess@FMSY)


SAMtool documentation built on Sept. 11, 2024, 8:07 p.m.