A threshold is a choice made before reading the metric. Moving it changes the exact confusion counts, so the table recomputes each operating point instead of echoing labels.
highlighted = computed this step
Thresholds are choices
The threshold is stated before the counts are read. This toy table uses thresholds 5, 3, and 1. Lowering the threshold marks more rows positive, so the confusion counts change by exact integer recomputation from the same scored rows.
thresholds 5,3,1
Counts move exactly
At threshold 5, the counts are TP=1, FN=2, FP=0, TN=3. At threshold 1, they become TP=3, FN=0, FP=2, TN=1. Nothing is interpolated between rows; each operating point is its own exact recount.
TP,FN,FP,TN recompute at each threshold
Summary
The threshold is chosen, not fitted inside this evaluation table. The diagram shows discrete exact operating points only; it does not draw a smooth curve or imply unshown threshold values.