: "We classified these journals into three categories: (a) FP journals published by for-profit publishers, (b) NFP journals managed by not-for-profit publishers (scientific societies, university presses, etc.), and NFPP journals published and distributed by FP firms on account of scientific societies....Our empirical investigation documents the following: [0] There exist large price differences across fields. [0] These differences seem to be correlated with the market power of publishers. The larger the concentration ratio, the larger the average price in a field, the price to which should be added the large difference between FPs, NFPPs and NFPs. [0] As a general rule, FP journals charge four times as much on average than NFP journals, for a given number of citations, age, language, number of articles, and field (or concentration ratio). Journals of scientific societies managed by FP publishers (NFPP) are twice as expensive as NFP journals (scientific societies exercise some control on prices). [0] Prices are positively correlated with quality measured by the number of citations they receive (even when citations are instrumented), and this effect is larger for FP journals....We take the first finding as indicative of the fact that substitution possibilities across journals are limited, allowing for a significant amount of discretion in the setting of journal prices....We confirm earlier research concerning the large price difference between FP and NFP journals, and show that prices of NFPP journals are somewhere in between. Moreover, we show that prices increase with citation counts and we have argued that costs should tend to fall when citation counts rise. This is consistent with "value-based pricing" (à la McCabe 0000, 0000) rather than with cost-based pricing, and is again indicative of publishers' ability to exercise discretion in price setting, because journals and papers are hardly substitutes, and researchers need all of them...." 