Figure 3.

Fitted vs. observed response variable values based on the models ZIP-W ${}^{b2}$ (panels in row 1), ZIP-W ${}^{c2}$ (panels in row 2), ZIP-W ${}^b$ (panels in row 3), ZIP-W ${}^c$ (panels in row 4), ZIP-O ${}^b$ (panels in row 5) and ZIP-O ${}^c$ (panels in row 6). The panels in the left column are for the full data. For ease of visualization, the panels in the right column display the results after suppressing the largest value of the observed response variable.