GlobalFishingWatch / treniformis

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Update the Fishing Queries #45

Open davidkroodsma opened 7 years ago

davidkroodsma commented 7 years ago

I recently explored what all the vessels who have very few positions are doing. Here are some of the data explorations:

Our previous algorithm included likely fishing vessels as only those that have at least 1000 positions in a year. I found it was better to count "active positions" (positions with a speed > .1 knots), thus ignoring vessels that stayed at port, and lower the threshold to 500 positions in a year. This way we include roughly 95% of the total fishing effort.

I also found that we should include vessels that broadcast that they are fishing vessels >99 percent of the time, as opposed to the previous 100% of the time. The reason is that due to errors in broadcast, some fishing vessels have a bad message where they don't broadcast that they are fishing vessels. Including these vessels increases the total number of fishing vessels by a few percentage points.

This updated version increases the number of fishing vessels by ~10,000 per year. It is currently in the branch version 1.0, and needs to be merged to master.

bitsofbits commented 7 years ago

@davidkroodsma, can we close this issue or it still active