They report false negative rate (FNR) here:

tantalor • today at 2:46 PM • 1 reply • view on HN

  Academic Writing  FNR=0.00%  N=48443
  Creative Writing  FNR=0.23%  N=41940
  RAID              FNR=0.93%  N=66855

Recall = 1 - FNR

cubefox • today at 5:12 PM

Yeah, that corresponds to a high value of my 1. The other three values are also important though.

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