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Build a multispecies fleet system from tables

Source: R/system.R
ms_system.Rd

Defines the stocks, métiers, catchability, fleet segments and costs that all other functions use.

Usage

ms_system(
  species,
  metiers,
  catchability,
  segments,
  cost_share = 0.4,
  effort_season_amp = 0,
  F_cap = Inf
)

Arguments

species

data frame, one row per stock, with columns species, r, K and price; optional code (short label), group, season_amp (0 = resident, 1 = absent at the low point), season_peak (month of highest availability), F_cap (cap on realised F in units of Fmsy, see ms_simulate()) and dep_init (starting B/K of simulations, default 1; set by ms_condition()).

metiers

data frame, one row per métier, with column metier; optional tactic, ground and cost (cost per day of a vessel with efficiency 1). Without cost, costs are cost_share times each métier's unfished revenue rate.

catchability

catchability of each stock in each métier: a matrix (métiers x stocks, with dimnames) or a data frame with a metier column and one column per stock.

segments

data frame, one row per fleet segment, with columns segment, loyalty (share of days on home métiers) and home (home métiers separated by ;, empty = all); optional efficiency (on home métiers, default 1), efficiency_away (default efficiency), cost_multiplier (daily cost relative to a vessel of efficiency 1, default efficiency), vessel_cv (spread of vessel efficiency within the segment, default 0.25), share_target (target share of days, used by ms_tune()) and capacity (registered days, the default fleet capacity of the segment, e.g. for the app).

cost_share

used when metiers has no cost column.

effort_season_amp

seasonal amplitude of effort (0 = equal months; effort peaks in July).

F_cap

cap on realised F (units of Fmsy) for stocks without an F_cap column value; Inf = no cap, 1.95 = floor at 0.05 Bmsy.

Value

An object of class ms_system.

See also

atlantic_system() for a ready-made example.

Examples

sys <- atlantic_system()
sys
#> <ms_system> 10 stocks, 6 metiers, 3 segments
#>   stocks:   DEC, PAC, SBR, HKE, COE, GFB, ALB, DOL, AMB, VMA 
#>   metiers:  Reef_shallow, Sediment_shallow, Pelagic_shallow, Reef_deep, Sediment_deep, Pelagic_deep 
#>   segment demersal   loyalty 0.80, efficiency 1.00, daily cost x0.634, home: Reef_shallow, Sediment_shallow, Reef_deep, Sediment_deep
#>   segment pelagic    loyalty 0.80, efficiency 1.00, daily cost x1.077, home: Pelagic_shallow, Pelagic_deep
#>   segment mixed      loyalty 0.00, efficiency 0.75, daily cost x0.843, home: Reef_shallow, Sediment_shallow, Pelagic_shallow, Reef_deep, Sediment_deep, Pelagic_deep