cpue()

[ibidyouadu]

A dreaded thing that comes up every so often is how we define CPUE. As of this writing, the best calculation for CPUE we have with OF data is

CPUE = avg(total catch weight per boat per month)

A cpue function would standardize the working definition of CPUE that we have as it changes over time (for example, in OurFish 2.0 we might have more complete data on fishers per trip, so the CPUE definition would make use of this value)

If we wanted the CPUE from Mozambique catches in 2022, where we define the unit effort in terms of boats and months (so that CPUE is in kg per boat per month), we could have something like

of <- getData("ourfish")
of <- of %>% dplyr::filter(country == "Mozambique", year = 2022)
moz22_cpue <- cpue(catch_data=of, effort=c("fisher_id", "yearmonth"))

There would be a default value for effort to standardize our CPUE definition, but it could be customized to suit specific needs (like donor reports asking for specific units)