Comparisons of photoionization models with different input parameters in the P₁ –P₂ diagram. The cyan model is our fiducial model. The red model has the fiducial abundances and depletion set, but uses the SED adopted by the B17 model. The purple model uses the fiducial SED, but adopts the abundances and depletion set of the B17 model. The blue model uses the fiducial SED, but adopts the abundances and depletion set of the D13 model. The modelsare interpolated and cut so that only the parts that cover the middle 98% of the data along the hidden P₃ axis are shown. The density distribution of the H II region sample is plotted in green and yellow, while the rest of the MaNGA sample is plotted in black and white.