Differential SFE per column density bin from YSO-counting in nearby clouds vs. column density compared to both the filament or transition model (black curve) and the ϵ_ff model (blue line). Left: comparison of both Class I-based (orange shading) and Class II-based (green shading) SFE estimates with the nominal models discussed in Sect. 6.1. Right: comparison of the Class I-based SFE estimates (orange shading) with the “best-fit” transition and ϵ_ff models (black and blue solid lines, see text). The nominal models shown in the left panel are displayed as dashed lines.