Fig 2. The log-sigmoid transformation of abundances allows the CRISPRi-DR model to factor in the non-linear effect of sgRNA strength on concentration dependence.

(A) Simulation of sgRNAs abundances for an ideal essential gene. Parameters used in simulation: H_s = −4, IC₅₀ = 0.25, K_s = −10 and H_d = −0.5 over a range of sgRNA efficiencies and drug concentrations. (B) When the log-sigmoid transformation of the abundances is applied, we see all the regression fits are parallel to one another, allowing to be fit by a single common slope, representing the concentration dependence over all sgRNAs, regardless of sgRNA efficiency.