Figure 3.

Relative precision of symptomatic case fatality ratio (sCFR) pyramidal estimators versus the single-level estimator $({\hat{p}}_{D|S})$, given similar budgets. Relative precision is measured with the standard error (SE) ratio, obtained by dividing the minimal SE of each pyramidal estimator by that of the single-level estimator. Recruitment costs are assumed to be equal at all surveillance levels of all estimation strategies. It can be noted from equation 4 that the SE ratio of 2 estimators that have the same budget C is independent of C.