FPR as a function of score threshold, separately for different negative components, for results obtained after 1st, 3rd, 7th, and 14th epochs of observation. TPR values corresponding to different score thresholds are marked on the top x-axis. The FPR for all three negative components – HSC variables, SN exploding in LRGs and spiral galaxies – gradually decreases with additional observations. However, it is clearly evident that SNe exploding in LRGs dominate the FPR budget, as they are more likely to be confused with the positive class.