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Reference data summary

EMW ref. id
"Estimated mean weight" reference id. References are assigned an id m where m is an integer starting with 1 for each EMW id. This is a hyperlink to screen 4.
FAO species category
A species or group of species reported in FAO FishStat aquaculture production statistics.
Species
The species for which the mean weight is estimated. This will be different from FAO species category in cases where the estimated mean weight applies to the smallest or largest species of a multi-species category.
Scientific name
The Scientific name for Species.
Lower (or upper) estimated mean weight (EMW)
The lower (or upper) end of the estimated mean weight range weight that would be estimated for this Species if based on this reference alone.
Used for lower or upper EMW figure?
This indicates whether the fish size data applies to both the lower and upper end of the estimated mean weight range, or just one of them. "Both" means it does e.g. "the average weight is 1-2 Kg". "Upper" means the fish size data applies to the upper end only of the range e.g. "most fish are harvested at less than 1 Kg". "Lower" means the fish size data applies to the lower end only e.g. "fish exceeding 2 Kg are commonly marketed".
Reference is for additional info only
Some references are used for additional information on identifying species within multi-species categories and not for estimating mean weights.
Reliability ranking of this method
This number indicates relative reliability of the method used in estimating the mean weight range from the fish size data. The lower this number, the better the data is likely to be.
Size type
Indicates whether the data used is a harvest, market, table or grow out size for farmed fish.
EMW method type
The derivation of estimated mean weight ranges from different types fish size data are called "methods". Different methods require different types of calculation. For example, estimates based on common lengths require calculations to convert lengths to weights (using length-weight formulae). The type of method used depends on the type of fish size data being used and determines the reliability ranking of the reference.