フリー問題

問題文

A binary classifier is run once over 200 cases. The confusion matrix records 60 true positives, 20 false positives, 40 false negatives and 80 true negatives. Which set of figures is right for this matrix, including the harmonic mean of the last two?

選択肢

1. The accuracy reaches 70 percent, the precision reaches 60 percent, and the recall reaches 75 percent, so the aggregate measure sits near 66.
2. The accuracy reaches 80 percent, the precision reaches 75 percent, and the recall reaches 70 percent, so the combined figure sits near 72.
3. The accuracy reaches 75 percent, the precision reaches 70 percent, and the recall reaches 60 percent, so the joint score sits near 65.
4. The accuracy reaches 70 percent, the precision reaches 75 percent, and the recall reaches 60 percent, so the harmonic mean sits near 67.