Cape Town procedure controls and default data object

sbt_ctp_controls() returns a fresh copy of the public constants used by the Cape Town procedure in CTP(). mpdat is the pre-built default list (the R equivalent of the original CTP.dat control file). These are management-procedure settings, rather than stock-assessment observations.

Usage

sbt_ctp_controls()

mpdat

Format

A named list containing the default values of every field described under Control fields.

Value

A named list containing the control fields described above. Use the function when a fresh copy is needed for a modified procedure run; mpdat contains the unmodified package defaults.

Details

The procedure combines three signals: standardised longline CPUE, gene-tagging abundance, and close-kin mark-recapture (CKMR) estimates of total reproductive output (TRO). The controls define the averaging periods, response curves, CKMR population model, and final TAC constraints.

Control fields

tau1: Number of recent completed years averaged for the CPUE signal.
Ilow, Ihigh: Lower and upper reference points for the standardised CPUE signal. Between them, the CPUE buffer is one.
alp1, bet1: Powers controlling the CPUE response below Ilow and above Ihigh, respectively.
wcpue1, wcpue2: CPUE gains used below and above the TRO rebuilding transition, respectively.
tau2: Number of recent gene-tagging estimates included in the weighted abundance signal.
N2low, N2high: Lower and upper gene-tagging abundance reference points, in numbers of fish. Between them, the gene-tagging multiplier is one.
alp, bet: Powers controlling the gene-tagging response below N2low and above N2high, respectively. They are mapped internally to the historical alp2 and bet2 names used by CTP().
tau3: Number of recent TRO estimates averaged for the CKMR level signal.
c1ref, c2ref: First year and exclusive upper year of the reference TRO period; the defaults therefore use 2003–2014.
tauck: Number of recent TRO estimates used to calculate the log-scale TRO trend.
gamma: Multiplier applied to reference TRO to define the rebuilding level.
lamtilde: Minimum log-TRO trend applied when the population is below the rebuilding level.
kappa: Steepness of the logistic transition between the below- and above-rebuilding control settings.
kck1, kck2: CKMR trend gains used below and above the rebuilding transition, respectively.
wCK: Weight applied to the CKMR contribution to the TAC multiplier.
peta: HSP detection adjustment applied multiplicatively in the CKMR observation model.
amin, amax: Minimum and maximum adult ages represented in the internal CKMR population model.
muchi0, sigmachi0: Mean and standard deviation of the initial logit-scale adult-mortality state.
Zmin, Zmax: Lower and upper bounds used to transform the adult total-mortality state.
Z30: Total mortality at age 30, used to interpolate mortality from age 25 to amax.
sigmachi: Annual innovation standard deviation for the adult- mortality state.
sigmaR, rhoR: Innovation standard deviation and AR(1) autocorrelation for recruitment.
qhsp: Multiplicative scale for expected HSP matches.
phi: Age-specific relative reproductive output for ages amin:amax, normalised to one at the oldest age.
TACmax: Absolute upper TAC bound, in tonnes.
maxChange_up, maxChange_down: Maximum permitted TAC increase and decrease at one procedure update, in tonnes.
minChange: Absolute TAC change, in tonnes, below which the TAC is left unchanged.

Examples

controls <- sbt_ctp_controls()
names(controls)
#>  [1] "tau1"           "wcpue1"         "wcpue2"         "Ihigh"         
#>  [5] "Ilow"           "alp1"           "bet1"           "tau2"          
#>  [9] "N2low"          "N2high"         "alp"            "bet"           
#> [13] "tau3"           "kck1"           "kck2"           "tauck"         
#> [17] "gamma"          "lamtilde"       "kappa"          "wCK"           
#> [21] "peta"           "c1ref"          "c2ref"          "amin"          
#> [25] "amax"           "muchi0"         "sigmachi0"      "Z30"           
#> [29] "Zmax"           "Zmin"           "sigmachi"       "sigmaR"        
#> [33] "rhoR"           "qhsp"           "phi"            "TACmax"        
#> [37] "maxChange_up"   "maxChange_down" "minChange"     
identical(controls, mpdat)
#> [1] TRUE