Close the boundary around one exact F-score summary.
highlighted = computed this step
Compare the two F-score fractions
Grid A gives 2 over 3. Grid B gives 1 over 2.
F one , A = 2 3 , F one , B = 1 2 F_{\text{one},A}={2\over3},\quad F_{\text{one},B}={1\over2} F one , A = 3 2 , F one , B = 2 1 F1 Score Exactly Exact F1 fractions from two confusion grids. two confusion grids with exact F1 fractions grid A grid A confusion grid actual pred P pred N P TP=2 FN=1 N FP=1 TN=1 precision and recall side labels rate fraction precision TP/(TP+FP) 2/3 = 2/3 recall TP/(TP+FN) 2/3 = 2/3 F1 denominator blocks 2TP=4 FP=1 FN=1 2TP+FP+FN=6 F1=4/6 = 2/3 grid B grid B confusion grid actual pred P pred N P TP=1 FN=2 N FP=0 TN=2 precision and recall side labels rate fraction precision TP/(TP+FP) 1/1 = 1 recall TP/(TP+FN) 1/3 = 1/3 F1 denominator blocks 2TP=2 FP=0 FN=2 2TP+FP+FN=4 F1=2/4 = 1/2 F1 is computed from displayed counts; denominator is 2TP plus FP plus FN does not claim: NOT best metric; NOT future performance NOT accuracy; NOT calibration; NOT fairness; NOT safety NOT generalization; NOT probability truth
No metric claim
This summary is exact arithmetic from the displayed grids. It does not choose a metric winner.
exact summary arithmetic only \text{exact summary arithmetic only} exact summary arithmetic only F1 Score Exactly Exact F1 fractions from two confusion grids. two confusion grids with exact F1 fractions grid A grid A confusion grid actual pred P pred N P TP=2 FN=1 N FP=1 TN=1 precision and recall side labels rate fraction precision TP/(TP+FP) 2/3 = 2/3 recall TP/(TP+FN) 2/3 = 2/3 F1 denominator blocks 2TP=4 FP=1 FN=1 2TP+FP+FN=6 F1=4/6 = 2/3 grid B grid B confusion grid actual pred P pred N P TP=1 FN=2 N FP=0 TN=2 precision and recall side labels rate fraction precision TP/(TP+FP) 1/1 = 1 recall TP/(TP+FN) 1/3 = 1/3 F1 denominator blocks 2TP=2 FP=0 FN=2 2TP+FP+FN=4 F1=2/4 = 1/2 F1 is computed from displayed counts; denominator is 2TP plus FP plus FN does not claim: NOT best metric; NOT future performance NOT accuracy; NOT calibration; NOT fairness; NOT safety NOT generalization; NOT probability truth
The honest boundary
This is exact count arithmetic only; it does not claim: NOT best metric; NOT future performance; NOT accuracy; NOT calibration; NOT fairness; NOT safety; NOT generalization; NOT probability truth.
same counts; exact F-score fractions \text{same counts; exact F-score fractions} same counts; exact F-score fractions F1 Score Exactly Exact F1 fractions from two confusion grids. two confusion grids with exact F1 fractions grid A grid A confusion grid actual pred P pred N P TP=2 FN=1 N FP=1 TN=1 precision and recall side labels rate fraction precision TP/(TP+FP) 2/3 = 2/3 recall TP/(TP+FN) 2/3 = 2/3 F1 denominator blocks 2TP=4 FP=1 FN=1 2TP+FP+FN=6 F1=4/6 = 2/3 grid B grid B confusion grid actual pred P pred N P TP=1 FN=2 N FP=0 TN=2 precision and recall side labels rate fraction precision TP/(TP+FP) 1/1 = 1 recall TP/(TP+FN) 1/3 = 1/3 F1 denominator blocks 2TP=2 FP=0 FN=2 2TP+FP+FN=4 F1=2/4 = 1/2 F1 is computed from displayed counts; denominator is 2TP plus FP plus FN does not claim: NOT best metric; NOT future performance NOT accuracy; NOT calibration; NOT fairness; NOT safety NOT generalization; NOT probability truth