Observed flux (gray) corresponding to the galaxies A, B, and C from the mock observation shown in Fig. 1. We show the 68% C.L. of the likelihood assuming the correct HII bubble location and radius in blue, $(R_{\mathrm{b}},{\mathcal{O}}_{\mathrm{b}})=(R_{\mathrm{b}}^{\mathrm{true}},{\mathcal{O}}_{\mathrm{b}}^{\mathrm{true}})$. We show the 68% C.L. of the flux likelihood assuming the correct HII bubble location, but a slightly smaller radius in red, $R_{\mathrm{b}}=0.8R_{\mathrm{b}}^{\mathrm{true}}$.