DLMtool (version 5.2)

AvC_MLL: Average Catch with a size limit

Description

A example mixed control MP that uses the average catch output control MP together with a minimul size limit set at the size of maturity.

Usage

AvC_MLL(x, Data, reps = 100, plot = FALSE)

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?

Value

An object of class Rec with the TAC, SL slot(s) populated

Required Data

See '>Data for information on the Data object

AvC_MLL: Cat, LHYear, Year

Rendered Equations

See Online Documentation for correctly rendered equations

Details

The average catch method is very simple. The mean historical catch is calculated and used to set a constant catch limit (TAC). If reps > 1 then the reps samples are drawn from a log-normal distribution with mean TAC and standard deviation (in log-space) of 0.2.

For completeness, the TAC is calculated by:

$$\textrm{TAC} =\frac{\sum_{y=1}^{\textrm{n}}{C_y}}{\textrm{n}}$$

where \(\textrm{TAC}\) is the the mean catch recommendation, \(n\) is the number of historical years, and \(C_y\) is the catch in historical year \(y\).

The size of retention is set to the length of maturity.

This MP has been included for demonstration purposes of a mixed control MP.

See Also

Other Average Catch MPs: AvC, DCACs

Examples

# NOT RUN {
Rec <- AvC_MLL(1, DLMtool::Cobia, reps=1000, plot=TRUE) # 1,000 log-normal samples with CV = 0.2
# }