اقتصاد کلان اقتصاد باز جدید : یک بررسی

Since the 1995 publication of Obsteld and Rogoff’s Redux model, there has been an outpouring of research on open-economy dynamic general equilibrium models that incorporate imperfect competition and nominal rigidities. This paper offers an interim survey of this recent literature.

This article surveys some recent efforts to develop a new workhorse model for open-economy macroeconomic analysis.1 The unifying feature of this emerging literature is the introduction of nominal rigidities and market imperfections into a dynamic general equilibrium model with well-specified microfoundations. Imperfect competition – whether in product or factor markets – is a key ingredient in the new models. One reason is that, in contrast to perfect competition (under which agents are price-takers), monopoly power permits the explicit analysis of pricing decisions. Second, equilibrium prices set above marginal cost rationalize demand-determined output in the short run, since firms are not losing money on the additional production.2 Third, monopoly power means that equilibrium production falls below the social optimum, which is a distortion that can potentially be corrected by activist monetary policy intervention. This approach offers several attractions. The presentation of explicit utility and profit maximization problems provides welcome clarity and analytical rigor. Moreover, it allows the researcher to conduct welfare analysis, thereby laying the groundwork for credible policy evaluation. Allowing for nominal rigidities and market imperfections alters the transmission mechanism for shocks and also provides a more potent role for monetary policy. In this way, by addressing issues of concern to policymakers, one goal of this new strand of research is to provide an analytical framework that is relevant for policy analysis and offers a superior alternative to the Mundell–Fleming model that is still widely employed in policy circles as a theoretical reference point. In describing the findings of this research program, I focus almost exclusively on the analysis of monetary shocks. This reflects the emphasis in the literature, for the role of nominal rigidities is most starkly illustrated in the case of monetary shocks and it is this kind of disturbance that flexible-price models are least well-equipped to handle. Obstfeld and Rogoff (1995a) is commonly recognized as the contribution that launched this new wave of research and this paper is reviewed in Section 2 below. An important precursor was the paper by Svensson and van Wijnbergen (1989). This paper is a manifesto for sticky-price models that have solid microfoundations and are firmly embedded in an intertemporal setting and much of the analytic structure of that paper has been adopted in the more recent literature. However, these authors modelled home and foreign outputs as stochastic endowments and the subsequent literature has devoted much more attention to endogenizing the production side of the economy. Krugman (1995) also signalled many of the research issues which have received attention in this new literature. Finally, it should be noted that the research program described here is very much linked to developments in closed-economy macroeconomics. There is a sense that macroeconomists are converging on a common modelling framework that integrates imperfect competition and nominal rigidities into dynamic general equilibrium models. This recent development has been labelled ‘neomonetarism’ by Kimball (1995) and the ‘new neoclassical synthesis’ by Goodfriend and King (1997). The rest of the paper is organized as follows. The Obstfeld–Rogoff Redux model is briefly outlined in Section 2. Section 3 reviews alternative approaches to modelling nominal rigidity. The impact of market segmentation and pricing to market behavior is discussed in Section 4. We turn to the specification of preferences and technology in Section 5. Section 6 introduces variation in financial structure. The analysis of international policy interdependence is reviewed in Section 7. Section 8 discusses theoretical frameworks that explicitly allow for uncertainty and Section 9 alternative approaches to modelling market structure. Small open economy models are the subject of Section 10. Section 11 reviews the body of empirical work associated with this new research program. Section 12 concludes.

This paper has reported on new literature that is attempting to reshape how international macroeconomics is done. Although the impact effects of shocks on real variables in many cases are largely similar to those predicted by traditional reduced-form models, the intertemporal nature of the recent models also allow the tracking of dynamic effects. Perhaps more importantly, the solid microfoundations embedded in these models permit welfare analysis, which can generate some surprising results. In turn, welfare analysis opens the door to rigorous policy evaluation, providing new foundations for the analysis of international policy interdependence. In related fashion, the stochastic versions of these new models are well-designed for making meaningful comparisons across different policy regimes. As is readily apparent from this survey, many welfare results are highly sensitive to the precise denomination of price stickiness, the specification of preferences and financial market structure. For this reason, any policy recommendations emanating from this literature must be highly qualified. This is an issue of some concern, since the new open economy macroeconomics will be of only limited interest in policy circles unless researchers converge on a ‘preferred’ specification that is buttressed by extensive supporting empirical evidence. For all that, the many unanswered questions that remain should ensure that this burgeoning field is likely to grow yet further in the coming years.