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941.
Summary. We develop a method of assigning unique prices to derivative securities, including options, in the continuous-time finance model developed in Raimondo (2001). In contrast with the martingale method of valuing options, which cannot distinguish among infinitely many possible option pricing processes for a given underlying securities price process when markets are dynamically incomplete, our option prices are uniquely determined in equilibrium in closed form as a function of the underlying economic data.Received: 14 April 2003, Revised: 7 January 2004, JEL Classification Numbers: G13, D52.This paper is dedicated to Birgit Grodal, whose strength and character we greatly admire. We are very grateful to Darrell Duffie, Steve Evans, Botond Koszegi, Roger Purves, Jacob Sagi, Chris Shannon, Bill Zame and an anonymous refereee for very helpful discussions and comments. The work of both authors was supported by Grant SES-9710424, and Andersons work was supported by Grant SES-0214164, from the National Science Foundation.  相似文献   
942.
The purpose of this study is to examine the effects of State regulation that determines the extent of professional independence of advanced practice nurses (APNs). We find that in States where APNs have acquired a substantial amount of professional independence, the earnings of APNs are substantially lower, and those of physicians assistants (PAs) are substantially higher, than in other States. These results are striking since PAs are in direct competition with APNs; the only real operational difference between these groups is that PAs are salaried employees who must work under the supervision of a physician. The implication is that physicians have responded to an increase in professional independence of APNs by hiring fewer APNs and more PAs. The finding that earnings of APNs decline when they attain more professional autonomy vis-à-vis physicians reinforces work by Sass and Nichols on physical therapists.The content is the responsibility of the authors and does not represent official positions of the Federal Reserve Bank of St. Louis or the Federal Reserve SystemJEL classification: I11, I18, J31, J44, L51  相似文献   
943.
This paper applies smooth transition models to capture the nonlinear behavior in the imports data of six major European economies and to assess whether such nonlinearities are related to business cycle asymmetries. Two classes of switch between regimes are considered: endogenously determined transition that assumes nonlinearities are generated by idiosyncratic components specific to foreign trade, and exogenous transition based on GDP growth as a more direct indicator of the cyclical state of the economy. The results support the proposition that the dynamics of imports are nonlinear. In Belgium, France, Spain, and the United Kingdom, regimes change over the business cycle, while in Germany and Italy the switch between regimes is endogenous. National characteristics play a role in defining the position of extreme regimes, the smoothness of the transition, and local dynamics within each state.Previous versions of this article have been presented at the 57th International Atlantic Economic Conference (Lisbon, Portugal, March 10–14, 2004) and at the VII Encuentro de Economía Aplicada (Vigo, Spain, June 3–5, 2004). The authors thank the conference participants and an anonymous referee for their comments.  相似文献   
944.
Recently economists have become interested in why people who face social dilemmas in the experimental lab use the seemingly incredible threat of punishment to deter free riding. Three theories with evolutionary microfoundations have been developed to explain punishment. We survey these theories and use behavioral data from surveys and experiments to show that the theory called social reciprocity in which people punish norm violators indiscriminately explains punishment best.JEL Classification: C91, C92, D64, H41 Correspondence to: Jeffrey P. CarpenterWe thank Carolyn Craven, Corinna Noelke and two referees for comments, and Middlebury College for financial assistance. In addition, Carpenter acknowledges the support of the National Science Foundation (SES-CAREER 0092953).  相似文献   
945.
This paper empirically investigates the development of cross-country differences in energy- and labour productivity. The analysis is performed at a detailed sectoral level for 14 OECD countries, covering the period 1970–1997. A σ-convergence analysis reveals that the development over time of the cross-country variation in productivity performance differs across sectors as well as across different levels of aggregation. Both patterns of convergence as well as divergence are found. Cross-country variation of productivity levels is typically larger for energy than for labour. A β-convergence analysis provides support for the hypothesis that in most sectors lagging countries tend to catch up with technological leaders, in particular in terms of energy productivity. Moreover, the results show that convergence is conditional, meaning that productivity levels converge to country-specific steady states. Energy prices and wages are shown to positively affect energy- and labour-productivity growth, respectively. We also find evidence for the importance of economies of scale, whereas the investment share, openness and specialization play only a modest role in explaining cross-country variation in energy- and labour-productivity growth.   相似文献   
946.
We study the distribution of basic scientific research across countries and time, and explain the process that resulted in the United States becoming the undisputed leader in basic research. Our study is based on the records of scientific awards, and on the data of global economic trends. We investigate the degree to which scale/threshold effects account for the number of prizes won. We constructed a stylized model, predicting a non-linear relationship with lagged relative GDP as an important explanatory variable of a country’s share of prizes. Our empirical research findings find support for these predictions and the presence of a “winner-takes-all” effect.   相似文献   
947.
In 2003 Japan proposed a Climate Change Tax to reduce its CO2 emissions to the level required by the Kyoto Protocol. If implemented, the tax would be levied on fossil fuel use and the revenue distributed to encourage the purchase of energy efficient equipment. Analysis using the MIT Emissions Prediction and Policy Analysis (EPPA) model shows that this policy is unlikely to bring Japan into compliance with its Kyoto target unless the subsidy encourages improvement in energy intensity well beyond Japan’s recent historical experience. Similar demand-management programs in the US, where there has been extensive experience, have not been nearly as effective as they would need to be to achieve energy efficiency goals of the proposal. The Tax proposal also calls for limits on international emission trading. We find that this limit substantially affects costs of compliance. The welfare loss with full emissions trading is 1/6 that when Japan meets its target though domestic actions only, the carbon price is lower, and there is a smaller loss of energy-intensive exports. Japan can achieve substantial savings from emissions trading even under cases where, for example, the full amount of the Russian allowance is not available in international markets.  相似文献   
948.
Economic Growth with Imperfect Protection of Intellectual Property Rights   总被引:4,自引:0,他引:4  
This paper examines the growth effects of intellectual property right (IPR) protection in a quality-ladder model of endogenous growth. Stronger IPR protection, which reduces the imitation probability, increases the reward for innovation. However, stronger protection also gradually reduces the number of competitive sectors, in which innovation is easier than in monopolistic sectors. With free entry to R&D, the number of researchers in each remaining competitive sector increases, but the concentration of R&D activity raises the possibility of unnecessary duplication of innovation, thereby hindering growth. Consequently, imperfect rather than perfect protection maximizes growth. Welfare and scale effects are also examined.  相似文献   
949.
950.
The foundation upon which accounts of policy-motivated behaviorof Supreme Court justices are built consists of assumptionsabout the policy preferences of the justices. To date, mostscholars have assumed that the policy positions of Supreme Courtjustices remain consistent throughout the course of their careersand most measures of judicial ideology—such as Segal andCover scores—are time invariant. On its face, this assumptionis reasonable; Supreme Court justices serve with life tenureand are typically appointed after serving in other politicalor judicial roles. However, it is also possible that the worldviews,and thus the policy positions, of justices evolve through thecourse of their careers. In this article we use a Bayesian dynamicideal point model to investigate preference change on the USSupreme Court. The model allows for justices' ideal points tochange over time in a smooth fashion. We focus our attentionon the 16 justices who served for 10 or more terms and completedtheir service between the 1937 and 2003 terms. The results arestriking—14 of these 16 justices exhibit significant preferencechange. This has profound implications for the use of time-invariantpreference measures in applied work.  相似文献   
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