DLMtool (version 5.2)

Rcontrol: Intrinsic rate of Increase MP

Description

An MP proposed by Carl Walters that modifies the TAC according to trends in apparent surplus production that includes information from a demographically derived prior for intrinsic rate of increase

Usage

Rcontrol(x, Data, reps = 100, plot = FALSE, yrsmth = 10, gg = 2,
  glim = c(0.5, 2))
Rcontrol2(x, Data, reps = 100, plot = FALSE, yrsmth = 10, gg = 2,
  glim = c(0.5, 2))

Arguments

x

A position in a data-limited methods data object

Data

A data-limited methods data object

reps

The number of stochastic samples of the MP recommendation(s)

plot

Logical. Show the plot?

yrsmth

The number of years for smoothing catch and biomass data

gg

A gain parameters

glim

Limits for the change in TAC among years

Value

An object of class Rec with the TAC slot populated with a numeric vector of length reps

Functions

• Rcontrol: Base version Rcontrol

• Rcontrol2: This is different from Rcontrol because it includes a quadratic approximation of recent trend in surplus production given biomass

Required Data

See '>Data for information on the Data object

Rcontrol: Abun, Cat, Dep, FMSY_M, Ind, L50, MaxAge, Mort, Year, steep, vbK, vbLinf, vbt0, wla, wlb

Rendered Equations

See Online Documentation for correctly rendered equations

Details

The TAC is calculated as: $$\textrm{TAC} = \textrm{SP} (1-gG)$$ where \(g\) is a gain parameter, \(\textrm{SP}\) is estimated surplus production, and \(G\) is: For Rcontrol: \(G = r (1-2D)\) where \(r\) is the estimated intrinsic rate of increase, and \(D\) is assumed depletion.

For Rcontrol2: \(G = r - 2bB_\textrm{hist}\) where \(B_\textrm{hist}\) is the smoothed biomass overlast yrsmth years and: $$b = \sum{\frac{\textrm{SP}}{B_\textrm{hist}} - r} \frac{\sum{B_\textrm{hist}}}{\sum{B_\textrm{hist}^2}} $$.

The TAC is subject to conditions limit the maximum change from the smoothed catch over the last yrsmth years by the glim argument, e.g, default values of glim = c(0.5, 2) means that maximum decrease in TAC is 50 is 2 x average catch.

References

Made-up for this package.

See Also

Other Surplus production MPs: Fadapt, SPMSY, SPSRA, SPmod, SPslope

Examples

# NOT RUN {
Rcontrol(1, Data=DLMtool::Atlantic_mackerel, plot=TRUE)
Rcontrol2(1, Data=DLMtool::Atlantic_mackerel, plot=TRUE)
# }