I don’t understand this heuristic and I think it might be a bit garbled. Any idea what the author meant? How do you get 1000?

> A good rule of thumb is that you’ll want ten data points per significant digit of your evaluation metric. So if you want to distinguish 91% accuracy from 90% accuracy, you’ll want to have at least 1000 data points annotated. You don’t want to be running experiments where your accuracy figure says a 1% improvement, but actually you went from 94/103 to 96/103.