Fpa {icesAdvice}

Fpa from Flim

Description

Calculate the value of Fpa from Flim and sigmaF.

Usage

Fpa(Flim, sigmaF)

Arguments

Flim

the value of the Flim reference point.

sigmaF

the estimation uncertainty in F (standard error of logF in the terminal year).

Value

Value of Fpa.

Note

The purpose of PA reference points is to apply a precautionary approach in fisheries management.

By comparing the current F to Fpa, one can answer the question: are we at least 95% sure that F is below Flim, given the estimation uncertainty?

The ICES (2017) technical guidelines define Fpa as:

F_\mathrm{pa} = F_\mathrm{lim} \exp(-1.645\sigma_F)

The Fpa function can also be used to calculate reference points based on harvest rate: Hpa from Hlim and sigmaH.

Author(s)

Arni Magnusson.

References

ICES (2017) ICES fisheries management reference points for category 1 and 2 stocks. doi: 10.17895/ices.pub.3036ICES Advice Technical Guidelines 12.4.3.1.

See Also

Bpa calculates that reference point from Blim and sigmaB.

sigmaPA calculates the implicit sigma from PA reference points.

icesAdvice-package gives an overview of the package.

Examples

Fpa(0.90, 0.15)