Gcontrol {DLMtool} | R Documentation |
A harvest control rule proposed by Carl Walters that uses trajectory in inferred surplus production to make upward/downward adjustments to TAC recommendations
Gcontrol( x, Data, reps = 100, plot = FALSE, yrsmth = 10, gg = 2, glim = c(0.5, 2) )
x |
A position in the data object |
Data |
A data object |
reps |
The number of stochastic samples of the MP recommendation(s) |
plot |
Logical. Show the plot? |
yrsmth |
The number of years over which to smooth catch and biomass data |
gg |
A gain parameter |
glim |
A constraint limiting the maximum level of change in quota recommendations |
The TAC is calculated as:
\textrm{TAC} = \textrm{SP} ≤ft(1-gG\right)
where \textrm{SP} is the predicted surplus production for the next year,
g is a gain parameter, and G is the slope of surplus production
as a function of biomass over the last yrsmth
years.
The change in TAC is bounded by the glim
argument, which by default does not allow
the TAC to decrease by more than half or increase more than twice the last annual catch.
An object of class Rec-class
with the TAC
slot populated with a numeric vector of length reps
See Data-class
for information on the Data
object
Gcontrol
: Abun, Cat, Ind, Year
See Online Documentation for correctly rendered equations
C. Walters and T. Carruthers
Carruthers et al. 2015. Performance evaluation of simple management procedures. ICES J. Mar Sci. 73, 464-482.
Other Index methods:
GB_slope()
,
GB_target()
,
ICI()
,
Iratio()
,
Islope1()
,
Itarget1_MPA()
,
Itarget1()
,
ItargetE1()
Gcontrol(1, Data=MSEtool::Atlantic_mackerel, plot=TRUE)