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West Central Pacific Ocean Bigeye Tuna (WCPO BET) Weight Frequency Data

wcpo_bet_wf.Rd

Weight frequency composition data extracted from MFCL (Multifan-CL) frequency files and prepared for RTMB (R Template Model Builder) stock assessment modeling. Observations are organized by fishery, year, month, and 1 kg weight bins.

Usage

wcpo_bet_wf

Format

A data.table with 7 columns: year (integer), month (numeric), ts (integer), fishery (numeric), bin (integer), value (numeric), week (numeric). Multiple rows per fishery-year-month (one per 1 kg weight bin).

Source

Extracted from MFCL (Multifan-CL) model frequency file outputs and prepared for RTMB model input.

Details

Data workflow

Preparation steps:

  1. Extract weight composition data from MFCL frequency file using wtfrq() - Returns wide-format data with weight bins as columns (1, 2, 3, ... 200 kg) - Observations grouped by fishery-year-month

  2. Reshape to long format (one row per fishery-year-month-weight bin combination)

  3. Merge with timestep table to add model timestep indexing consistent with catch/CPUE

  4. Save as long-format data for RTMB model input

Output columns

year

Calendar year (1952-2018). Integer.

month

Fishing quarter month (2, 5, 8, 11 representing Q1-Q4 approx.). Numeric.

ts

Model timestep number (1-268 for 67 years × 4 quarters). Integer.

fishery

MFCL fleet index (1-15). Numeric.

bin

Weight bin (kg). 1 kg bins: 1, 2, 3, ... 200. Integer.

value

Observations in this weight bin. Numeric.

week

Temporal indicator within quarter (typically 1 for aggregated data). Numeric.

Notes

  • MFCL data uses 1 kg weight bins (1, 2, 3, ... 200 kg)

  • Data from wtfrq() represents observed weight frequency

  • Sum of values across bins per fishery-year-month instance gives total input sample size

  • Bin values are left as counts for RTMB to handle (divide by sample size if proportions needed)

Examples

if (FALSE) { # \dontrun{
  data(wcpo_bet_wf)
  str(wcpo_bet_wf)
  # View sample data
  head(wcpo_bet_wf)
  # Get total sample size per fishery-year-month
  wcpo_bet_wf[, .(total_n = sum(value)), by = .(year, month, fishery)]
} # }