Figure 3. Neutralization outcomes and NP computation for a typical serum, SA.C37.

This serum was chosen for illustration because it represents the median serum potency. (a) Outcomes for each of 225 viruses are either neutralized (ID50 >50, red) or not (ID50 ≤50, black) and are scattered noisily over virus mean ID50s, as in the hypothetical example (Figure 1c). (b) Beeswarm plot of the same data summarizes the NI distribution (tier-scaled geometric mean ID50 per virus) by outcome. The χ² p-value for significance of the slope is 4.79 × 10⁻¹². A superimposed curve shows the inferred logistic function, and a vertical line indicates the NP at 2.5. Symbol color indicates virus neutralization sensitivity, as in Figure 2a.