MQMF (version 0.1.1)

domed: domed calculates domed selectivity curves

Description

domed uses 6 parameters and a set of mean size or age classes to calculate a domed selectivity curve with a maximum of 1.0 (rescaling can be done outside the function), but has parameters for the selectivity of the initial and final size/age classes. There is an ascending limb and a descending limb with the potential of a plateau in between. The six parameters are 1) the age/size where selectivity first becomes 1.0, 2) the size/age where selectivity first begins to decline, 3) the steepness of the ascending limb, 4) the steepness of the descending limb, 5) the selectivity of the first age/size class, and 6) the selectivity of the last age/size class.

Usage

domed(p, L)

Arguments

p

a vector of six parameters.

L

a vector of the mean of nL age/size classes

Value

a vector of selectivities

References

Methot, R.D. and C.R, Wetzel (2013) Stock synthesis: A biological and statistical framework for fish stock assessment and fishery management. Supplementary material, Appendix A. Equs A1.30 onwards. Fisheries Research 142:86-99.

Examples

# NOT RUN {
  L <- seq(1,30,1)
  p <- c(10,11,16,33,-5,-2)
  sel <- domed(p,L)
  plot1(L,sel,xlab="Age",ylab="Selectivity",lwd=2)
# }