Table 2. Performance of proxy predictors at the 10% surveillance threshold.

Model 1 predicted the fate of a cluster using the top two predictors in our best fit model. The two proxy models used data from two time points, when the cluster reached relative frequencies of 6% (t₁) and 10% (t₂). Model 2 considered the time elapsed between and the number of competing expanding clusters. Model 3 considered the relative fold change in the focal cluster between the two time points and the population-wide variance in fold change. Performance values are the median of five-fold cross-validation.

Model	Type	AUC	PPV	Sensitivity
1. Rc/〈R〉+var(R)	Actual	0.88	0.81	0.89
2. ${\delta }_{\mathrm{c}}\left(t_1,t_2\right)+N_{{\mathrm{\Delta }}_j(t_1{t}_2)>1}$	Proxy	0.78	0.74	0.87
3. χc(t1,t2)+var(Δj(t1t2))	Proxy	0.67	0.66	0.95