The absolute fluxes of H₂O (top left) and C₂H₂ (top right) as a function of stellar luminosity. The fluxes are determined after normalizing the spectra to a distance of 120 pc. The line-to-continuum ratio for H₂O and C₂H₂ as a function of stellar luminosity are shown in the bottom left and right, respectively. Upper limits (downward triangles) are the 3σ fluxes. Error bars are smaller than the points for most targets. The blue points are the T Tauri sample and the red points are the VLMS targets. The PCCs and p-values can be found for each panel. Significant correlations (p-value<0.05) are provided in bold. $F_{{\text{H}}_2\text{O}}$ vs. L, (top left) and C₂H₂ line-to-continuum ratio vs. L, (bottom right) have the strongest correlations.