Figure 4. Number of articles published and two metrics of payoff to faculty for publishing in open-access journals (Journal Impact Factor™, average citations per year), as a function of article processing charges (in US$).

Blue trendline shows a simple linear regression including all journals, whereas the red trendline shows the relationship when the outlier journals Science and Nature are excluded from the analysis. Journals falling well away from the main cloud of journals (i.e., additional outliers) are labeled for discussion in the text.