mizer course - Create your first model

[giscus[bot]]

mizer course - Create your first model

https://course.mizer.sizespectrum.org/build/create-first-model.html

[Raquel-RuizDiaz]

Hi!, Quick question:
Shouldn't you include "calibrate biomass" in this iteration as well?

cur_model <- cur_model |>
matchBiomasses() |> steady() |> matchBiomasses() |> steady() |>
matchBiomasses() |> steady() |> matchBiomasses() |> steady() |>
matchBiomasses() |> steady() |> matchBiomasses() |> steady() |>
matchBiomasses() |> steady() |> matchBiomasses() |> steady() |>
matchBiomasses() |> steady() |> matchBiomasses() |> steady()

[gustavdelius]

Hi Raquel. That is a very useful question. I usually use calibrateBiomass() when also on average the observed biomasses are either significantly above or below the model biomasses. If some species are above and some below so that the average does not differ significantly then calibrateBiomass() has little effect, so I often don't bother. But you are right that it would not hurt to include it in the iteration.

[Xiaofan-Hong]

Hi!, if I use calibrateBiomass(), is that mean I don't need to calibrate the maximum recruitment or the erepro? I am sorry for this fool question.

[gustavdelius]

Hi Xiaofan. You do indeed not need to think about R_max or erepro. Those are two parameters which one does not usually know. So the approach we have been following in this course is to instead use the observed biomass and the resilience to fishing to fix the reproduction parameters.