Dominant area for the trip in FT table

[luciazarauz]

Dear core group,

we are using H3 for our onboard sampling scheme. And in table FO, we are reporting the area of each sampled haul.

However, we have realized that in the discards estimates we are asigning all the sampling to the dominant area of each trip. And we cannot report that information in H3 (as fas as we can see)

Would it be possible to add a FTarea variable (similar to LEarea), to assign each trip with a dominant area?

The other option we are considering is to report in table FO, for all hauls, just the dominant area. But it is a pity that this option would imply to lose valuable information, that could be used to explore alternative raising methods.

thank you very much

best regards

[davidcurrie2001]

Could you add a trip-level FO record which would record the dominant area? (As an example we have a trip-level FO record for our biological sampling, and also the haul level FO records for our length-frequency data.)

[luciazarauz]

Hi,
Sorry, I don't understand very well the proposed solution.

Do you mean having in our "Onboard sampling programme", for the same sampled trip,
one trip-level FO record with information about the dominant area, and no child records;
and several trip-level FO records, one for each haul, with the rest of the tables nested (SS, SS, FM)?

thanks

[davidcurrie2001]

Yes - do you think that could work?

Alternatively can you calculate the dominant area for each trip during the estimation process? Or is the dominant area for a trip decided using some information that isn't present in the RDBES data?

[luciazarauz]

ok.
The dominant area for a trip is actually coming from the official data, and it is not present in the RDBES data.

so... we can try the option of having one extra trip-level FO table. I think it could work, as it is a way of including the information that we need. However, I also think that it complicates a bit the structure of the hierarchy and the estimations.

But we can try :-)

Thanks!

[davidcurrie2001]

One other "hack" that might be easier in the short term is to record the dominant area in the stratum name of the FT records. (This assumes you're not already recording stratification information for the FT records.) It's not really what the field is for but might provide a quick fix.

The Core Group will also discuss your request for an FTarea field and see if it can be added to the data model.

[luciazarauz]

I like that one :-)

[HenrikK-N]

Dominant area is requested to be added to the Fishing Trip table, but potentially also the dominant gear, metier6, FOselectionDevice, quarter, FOmeshSize ect. could also be requested. In this light it would be an argument for adding a FO record with FOaggregationLevel Trip (Aggrgation level: H=haul. T=trip) and fill-in dominant area and others if needed, and not add a dominant area to the Trip table.
The issues will be closed when the text have been added to the documentation.