MQMF (version 0.1.1)

pttuna: pttuna is yellowfin tuna fishery data from Pella-Tomlinson 1969

Description

pttuna is yellowfin tuna fishery data from Pella-Tomlinson's (1969) classical paper describing their generalized surplus production model. This is the same data as contained in the schaef data-set, except it is extended from 1934 - 1967. Some of the values are slightly different, and their table rounds off the cpue estimates slightly differently but the catch and effort figures are theirs. It contains the year, the catch, the effort, and the cpue (which is just the total catch divided by the total effort, a ratio estimate). Initial parameter estimates close to the optimum values for the Schaefer model could be param <- log(c(r=0.28,K=2100000,Binit=2400000,sigma=0.16)). With this longer time-series the eventual MSY estimate was somewhat larger than when just the schaef data are used.

Format

A data.frame of fisheries data

year

the fishing year from 1934 - 1967

catch

the total annual catch, '000s of pounds

effort

the total effort as standard class 4 baitboat fishing days

cpue

the catch '000 pounds per standard class 4 day, a ratio cpue

Subjects

• surplus production modelling

• classical fisheries data

• Log-Normal likelihoods

Examples

# NOT RUN {
 data(pttuna)
 pars <- log(c(r=0.25,K=2.1e06,Binit=2.2e06,sigma=0.2))
 answer <- fitSPM(pars,pttuna,schaefer=TRUE,maxiter=1000)
 outfit(answer,title="Pella-Tomlinson Data",digits=4)
# }