mobw.kg: Mean body weight per month

In CatDyn: Fishery Stock Assessment by Catch Dynamics Models

Description

Using a data.frame with paired observations of length and weight of individuals, and a second data.frame with paired observations of length and month of individuals, predict the mean weight per month in kg and its standard error.

Usage

mobw.kg(par, lenw, lenm, method, span)

Arguments

par	Numeric vector length 2 with the initial values for parameters of the length-weight relationship.
lenw	Numeric data.frame with paired observations of length and weight (kg).
lenm	Numeric data.frame with paired observations of length and month in numeric format.
method	Character, the numerical method to fit the length-weight relationship. Use one of the following: BFGS,CG,Nelder-Mead,SANN.
span	The span parameter of the loess function to fit the length-month relationship.

Details

The length data in lenw and lenm must be in the same units.

Value

A data.frame with five columns: month, predicted mean weight from the length data and the length-weight relationship, its standard error, smoothed mean length from the loess fit of the length-month relationship, and its standard error.

Author(s)

Ruben H. Roa-Ureta (ORCID ID 0000-0002-9620-5224)

Examples

data(gayhakelm)
data(gayhakelw)
par <-  c(4e-4,2.9)
method <- "SANN"
span   <- 1
chihake.mobw <- mobw.kg(par=par, lenw=gayhakelw, lenm=gayhakelm,
                        method=method, span=span)

Example output

--------------------------------------------------------------
 Fishery Stock Assessment by Catch Dynamics Models
 CatDyn version 1.1-1 (built on 2018-12-18) is now loaded
--------------------------------------------------------------

CatDyn documentation built on May 2, 2019, 4:21 a.m.