search

ices-tools-dev / RDBES

The public repository of the RDBES development.
11 stars 5 forks source link

clarifications BVtypeAssess #129

Open edvinf opened 2 years ago

edvinf commented 2 years ago

I have some questions for the field BVtypeAssess.

As it is mandatory, and as it has no option for "Unknown" I gather it must be filled in for all measurements recored in a BV-table, so that the rows that are not used in assessment "refer" to those that are. If this is correct it could perhaps be stated explicitly in the field description.

As assessment methods may be subject to revision, the input data used may change. I gather the field BVtypeAssess must refer to current assessment methods. This could also be made explicit, if correct.

In addition I am interested in two clarifications:

If an assessment uses several kinds of input from commercial data (e.g. estimated numbers in groups defined by both age and length, or ages from some fleets and lengths from others), how should that be treated ?

how should this field be treated if measurements are recorded for stocks that are not currently assessed (e.g. bycatch or discard)?

davidcurrie2001 commented 2 years ago

"how should this field be treated if measurements are recorded for stocks that are not currently assessed (e.g. bycatch or discard)?" Two options jump to mind: a) add a code saying not "NotUsedForAssessment" or something similar, and just repeat the measured value, or b) just repeat the measured type and measured value.

HenrikK-N commented 2 years ago

If an assessment uses several kinds of measurement types from commercial data, it should not be a problem because each measurement type would be in it's own record, which would allow for different usages, so the assessment group can select the records/measurement types, which they will use in the assessment.

If the measurement type is not used for assessment the core group agreed to repeat the BiologicalMeasurementType from the BVtypeMeas.

edvinf commented 2 years ago

I think you have confirmed that the field refers to the assessment that is in place at the time of data submission, and it seems a the procedure has been defined for stocks not currently assessed, but neither is reflected in the documentation at the moment.

It is still not clear to me what to do when several parameters are used in assessment. Say both age and LengthTotal is used in assessment, but a user also wants to submit other parameters, say ForkLength, Sex, and Maturity. Should 'age 'or 'LengthTotal' be provided as BVtypeAssess for records of ForkLength, Sex, and Maturity.

To me it would make sense to provide TotalLength as the BVtypeAssess for the ForkLength-records, and unclear what to do with Sex and Maturity. This field seems to be motivated by the case where conversion of parameters are necessary for assessment, but the documentation may be confusing for the case when that is not necessary.

davidcurrie2001 commented 2 years ago

"This field seems to be motivated by the case where conversion of parameters are necessary for assessment, but the documentation may be confusing for the case when that is not necessary."

Yes that is exactly the case, and this would normally only be relevant for length, and weights I guess. So in the case of age and total length being used in the assessment then for your length BV rows, if you have measured fork length you would include your measured length (e.g. 150mm), your measured length type (e.g. fork length) the conversion factor (e.g. 1.2), and the type of measurement you are converting to for assessment (e.g. total length).

For your age rows I assume no conversion is necessary so you would have BV rows with a measured age (e.g. 3), the type of measurement (age in years), the conversion factor (1.0), and the type of measurement used in the assessment (e.g. age in years again).

You should never have a Sex/Maturity BV row being having an assessment type of total length or age since that wouldn't make any sense. The value in the BVtypeAssess field only refers to the BV row it is located in - it's not a general question about what types of data are used in the assessment.

We added some text to the description of this field on the data model spreadsheet yesterday to say that if no conversion is necessary then you should just repeat the same code in BVtypeAssess as you used in BVtypeMeasured - I hope this will clarify the issue. ( @HenrikK-N can you paste in the changed text to this issue? I pulled the latest spreadsheet from the Core group GitHub but it didn't seem to be there.)