Regime Effectiveness and the Oslo-Potsdam Solution: A Rejoinder to Oran Young

The Oslo-Potsdam solution to measuring regime effectiveness has been the subject of a fruitful scholarly exchange in Global Environmental Politics. ¹ From our point of view, the exchange has been very rewarding. In this rejoinder, we briefly summarize our own position and identify some remaining issues where our views seem to differ from Oran Young's.

First, we are encouraged by Young's evaluation that there are some attractive features about the Oslo-Potsdam solution—in particular that it offers a conceptual framework producing a single effectiveness score bounded between 0 and 1 which permits comparisons across regimes.

Second, Young is correct in pointing out that there are multiple alternative procedures for evaluating regime consequences. Among these procedures are process tracing and the regression approach proposed by Mitchell ² and others. ³ These procedures are certainly both legitimate and useful. Indeed, they have provided a basis for a number of excellent studies. It is worth noting, however, that most alternative approaches address only one of the two questions that form the basis for the concept of effectiveness. More precisely, they produce an assessment of what the situation would have been in the absence of the regime (a no-regime counterfactual) and compare it to the actual state of affairs. In essence, these alternative approaches typically try to determine whether—or to what extent—a given regime has made a difference. While this is no doubt an important agenda for research, it does not necessarily take us very far in the direction of determining whether the underlying problem that triggered the construction of the regime has been solved. For the latter purpose we need a notion of what constitutes a "good" or "optimal" solution as well. Note also that the unboundedness of these alternative approaches makes systematic comparison between cases difficult.

The proposed empirical approaches to the Oslo-Potsdam solution draw on the conceptual foundations of game-theoretical reasoning. There are alternative ways of translating this reasoning into empirical solutions, and we have outlined a variety of possible procedures, both for the no-regime counterfactual and for the collective optimum. ⁴ We eschew preferring one over other solutions, as there is too little empirical experience to warrant advocating one particular solution at the expense of others.

Third, although he does not explicitly say so, it appears that Young's position is consistent with the following view: (Empirically) identifying an "optimal" solution is unattainable in practice because, inter alia, different approaches for deriving collective optima are likely to produce different results. Thus, measuring regime effectiveness becomes a mission impossible. We are therefore well advised to give up on the task of computing effectiveness scores.

This seems to leave us with two remaining issues. The first is the extent to which the Oslo-Potsdam solution is "faulty". Young's assessment seems to be that our approach is fundamentally flawed. By contrast, we see it as imperfect. Second, there is the question of the best way forward. Young seems to imply that the problems encountered are so severe that one would be well advised to abandon not only the Oslo-Potsdam solution, but the entire project of assessing "effectiveness". Instead, one should turn to other ways of studying regime consequences. We consider this conclusion premature. We firmly believe that research on regime effectiveness has made significant progress in the past decade, and we are convinced that major new advances will be made in the years to come. We recognize that new solutions may differ from the Oslo-Potsdam formula. In the meantime, we recommend using the best tools available—and we believe the Oslo-Potsdam solution to be a serious candidate. At the same time, we encourage the research community to push forward—through refinements of existing approaches and by exploring new paths.

Finally, we believe that the best way forward should include...