LstepCC1 | R Documentation |
A management procedure that incrementally adjusts the TAC according to the mean length of recent catches.
LstepCC1( x, Data, reps = 100, plot = FALSE, yrsmth = 5, xx = 0, stepsz = 0.05, llim = c(0.96, 0.98, 1.05) ) LstepCC2( x, Data, reps = 100, plot = FALSE, yrsmth = 5, xx = 0.1, stepsz = 0.05, llim = c(0.96, 0.98, 1.05) ) LstepCC3( x, Data, reps = 100, plot = FALSE, yrsmth = 5, xx = 0.2, stepsz = 0.05, llim = c(0.96, 0.98, 1.05) ) LstepCC4( x, Data, reps = 100, plot = FALSE, yrsmth = 5, xx = 0.3, stepsz = 0.05, llim = c(0.96, 0.98, 1.05) )
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 |
Years over which to calculate mean length. |
xx |
Parameter controlling the fraction of mean catch to start using in first year |
stepsz |
Parameter controlling the size of update increment in TAC or effort. |
llim |
A vector of length reference points that determine the conditions for increasing, maintaining or reducing the TAC or effort. |
The TAC is calculated as:
\textrm{TAC} = ≤ft\{\begin{array}{ll} \textrm{TAC}^* - 2 S\textrm{TAC}^* & \textrm{if } r < 0.96 \\ \textrm{TAC}^* - S \textrm{TAC}^* & \textrm{if } r < 0.98 \\ \textrm{TAC}^* & \textrm{if } > 1.058 \\ \end{array}\right.
where \textrm{TAC}^* is (1-xx
) times average catch in the first year,
and previous catch in all projection years, S is step-size determined by stepsz
,
and r is the ratio of L_\textrm{recent} and L_\textrm{ave}
which are mean length over the most recent yrsmth
years and 2 x yrsmth
historical
years respectively.
The conditions are specified in the llim
argument to the function.
An object of class Rec-class
with the TAC
slot populated with a numeric vector of length reps
LstepCC1
: The least biologically precautionary TAC-based MP.
LstepCC2
: More biologically precautionary than LstepCC1
(xx
= 0.1)
LstepCC3
: More biologically precautionary than LstepCC2
(xx
= 0.2)
LstepCC4
: The most precautionary TAC-based MP.
See Data-class
for information on the Data
object
LstepCC1
: Cat, LHYear, ML, Year
LstepCC2
: Cat, LHYear, ML, Year
LstepCC3
: Cat, LHYear, ML, Year
LstepCC4
: Cat, LHYear, ML, Year
See Online Documentation for correctly rendered equations
T. Carruthers
Carruthers et al. 2015. Performance evaluation of simple management procedures. ICES J. Mar Sci. 73, 464-482.
Geromont, H.F., Butterworth, D.S. 2014. Generic management procedures for data-poor fisheries; forecasting with few data. ICES J. Mar. Sci. doi:10.1093/icesjms/fst232
LstepCC1(1, Data=MSEtool::SimulatedData, plot=TRUE) LstepCC2(1, Data=MSEtool::SimulatedData, plot=TRUE) LstepCC3(1, Data=MSEtool::SimulatedData, plot=TRUE) LstepCC4(1, Data=MSEtool::SimulatedData, plot=TRUE)
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