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A hockey stick (2 inflection points) HCR that accepts estimated level relative to reference level and modifies a proposed TAC based on control points for the x axis (est/ref) and y axis (fraction of TAC)

Usage

doHCR(trial_TAC, est, ref, CP = c(0, 1), CPy = c(0, 1))

Arguments

trial_TAC

Postitive real number, the proposed total allowable catch before HCR modification.

est

Positive real number on same scale as ref, the estimated stock level (e.g. mean current index level)

ref

Positive real number on same scale as est, a reference level of stock level (e.g. index level at BMSY)

CP

Vector of real numbers, 2 positions long (c(Lx, Ux)), the lower and upper control points of a hockey stick HCR on the xaxis (est/ref). Below Lx (est/ref < Lx) the TAC is trial_TAC x Ly. Above Ux (est/ref > Ux) the TAC is trial_TAC x Uy. Between the TAC is linearly ramped between these levels.

CPy

Vector of real numbers, 2 positions long (c(Ly, Uy)), the lower and upper control points of a hockey stick HCR on the yaxis (fraction of trial_TAC).

Value

A real number (TAC advice but theoretically could be used for effort, size limits etc).

Author

T. Carruthers