Islope4:
A management procedure that incrementally adjusts the TAC to maintain a constant CPUE or relative abundance index.
Description
The most biologically precautionary of two constant index / CPUE methods proposed by Geromont and Butterworth 2014. Tested by Carruthers et al. 2015
Usage
Islope4(x, DLM_data, reps = 100, yrsmth = 5, lambda=0.2,xx=0.4)
Arguments
x
A position in data-limited methods data object
DLM_data
A data-limited methods data object
reps
The number of TAC samples
yrsmth
Years over which to smooth recent estimates of surplus production
lambda
A gain parameter controlling the speed in update in TAC.
xx
Parameter controlling the fraction of mean catch to start using in first year
Value
A numeric vector of quota recommendations
Details
Tested by Carruthers et al. 2015.
References
Carruthers et al. 2015. Performance evaluation of simple management procedures. Fish and Fisheries. In press.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