estimate_tv_weight_at_age: Estimate time-varying weight at age
In pacific-hake/hake-assessment: Stock Assessment for Pacific Hake

estimate_tv_weight_at_age

R Documentation

Estimate time-varying weight at age

Description

Estimate time-varying weight at age

Usage

estimate_tv_weight_at_age(max_age = 15, first_year = 1975)

Arguments

max_age

An integer specifying the maximum age of the modeled data in the Stock Synthesis model. All age data beyond this will be assigned to the maximum age. This is typically the age beyond which data are sparse and weight and length are essentially the same across ages. The default is fifteen for Pacific Hake.

first_year

A four-digit integer specifying the first year of data in the assessment model. Sometimes weight-at-age data might begin before this year but the data are so sparse for other data that the model should not include this year as a separate year. For example, weight-at-age data for Pacific Hake start in the early 70s, which means that the cohorts are predicted for years prior to this, i.e., year - age, so we want to remove these early years with little data. The default for Pacific Hake is 1975.

Details

Predict weight-at-age for fishery and survey data without spatial information, where the model includes age, year, cohort, and sex. There is a smoother on age, year is modeled as a random effect, cohort is also a random effect, and sex is a linear predictor to estimate weight, i.e., (weight ~ 1 + s(age) + (1|fcohort) + (1|fyear) + sex).