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991.
In north-eastern Laos, the savannah grasslands of the Plain of Jars cover vast areas of potentially cultivable land. However, soil acidity, low inherent fertility, and the absence of alternatives to tillage represent significant constraints to the development of sustainable smallholder agriculture. Our objective was to evaluate the potential for conservation agriculture (CA) to enhance soil productivity and farming system profitability. A three-year rotation of rice/maize/soybean was tested under three fertilization levels and four agricultural systems: one conventional tillage-based (CT) system and three CA systems based on no-tillage with cover crops. After four cropping seasons, our results show that, compared with CT, CA systems led to similar-to-higher grain production, similar-to-higher profits, higher opportunity of livestock system intensification, and higher labour productivity regardless of fertilization levels. While CA represents a relevant alternative to current practices, our results suggest that its contribution to the emergence of a sustainable smallholder agriculture is conditioned by broader institutional transformations, including the enrolment of local manufacturers and traders for deploying no-till implements and seed market channels for cover crops, long-term public support to maintain active research and technical mentoring to farmers, and possibly the integration of ecosystem services in agricultural policy.  相似文献   
992.
哈萨克斯坦是我国在中亚地区重要经贸合作伙伴。为了帮助我国企业加大对哈萨克斯坦市场开拓力度,本文简要介绍了该国的贸易与投资环境,并对我国企业跨国经营应注意的问题给予了提示。  相似文献   
993.
We study appropriation strategies in common pool resources where extinction is a credible threat. Here we present an experimental study of the appropriation of common pool resources in a dynamic setting where resource availability depends on the initial environmental characteristics of the common resource and on human-induced resource depletion due to users’ appropriation patterns. Our results show that initial resource scarcity limits appropriation by inducing an initial caution among users that persists throughout of the game. Additionally, we find that subjects restrain their appropriation strategies when scarcity increases. However, this concern for resource scarcity is not enough to prevent resource depletion. Agents do not counteract the previous rounds’ appropriation strategies but follow the appropriation trend. High appropriation levels are followed by higher appropriation strategies, thus promoting the well known tragedy of the commons. Often concern for resource preservation is not great enough to limit appropriation.   相似文献   
994.
We study the productivity, financial and distributional performance of the United States Postal Service subsequent to its 1971 reorganization. We investigate the magnitude and the economic drivers of productivity change (technical change, change in cost efficiency, and scale economies), and we investigate the distribution of the financial benefits of productivity change (among consumers of postal services, postal employees and other resource suppliers, and residual claimants). We find improvements in technology to have been the main driver of, and diseconomies of scale to have been the main drag on, productivity change. We find labor to have been the main beneficiary, and consumers of postal services the main losers, from postal reorganization.   相似文献   
995.
We analyze the link between macroeconomic fundamentals and exchange rate dynamics in two new and two potential EU member states: Bulgaria, Romania, Croatia, and Turkey. Given the different institutional settings of the exchange rate market in the countries of interest, we follow two different modelling strategies. For Romania and Turkey, we evaluate possible exchange rate misalignments based on a monetary model of exchange rate determination. In the case of Bulgaria and Croatia, with currency board and narrow-band peg arrangements against the euro, we discuss possible exit strategies and quantitatively assess the effects of the peg arrangements by means of simulation.
Maria Antoinette SilgonerEmail:
  相似文献   
996.
The trade literature has long discussed the existence of some benefits attributed to exporting (learning-by-exporting), among others, the improvement in survival chances. This paper examines whether exporting SMEs enjoy better survival prospects than non-exporting SMEs. We investigate the determinants of survival of exporting and non-exporting SMEs and explore whether the exporting behaviour plays a significant role in explaining their probability of exit. For this purpose, we estimate discrete time proportional hazard models that account for unobserved individual heterogeneity. The dataset is a sample of Spanish manufacturing SMEs drawn from the Encuesta sobre Estrategias Empresariales (ESEE) for 1990–2002. After controlling for firm, industry and economy characteristics, we find evidence supporting the existence of a sizeable “surviving-by-exporting” effect. That is, exporting SMEs face a significantly lower probability of failure than non-exporters.  相似文献   
997.
We analyse a model of partially revealing, rational expectations equilibrium with diverse information, endogenous beliefs formation and uncertain distribution of risk aversion. More risk averse agents are then more optimistic. Such a positive correlation is important for collective decision analysis.  相似文献   
998.
This paper investigates the relationship between patents and research and development expenditures using new longitudinal patent data at the firm level for the U.S. manufacturing sector from 1982 to 1992. The paper also develops a new class of count panel data models based on series expansion of the distribution of individual effects. Estimation results from various distributed lag and dynamic multiplicative panel count data models show that the contemporaneous relationship between patenting and R&D expenditures continues to be strong, accounting for over 60% of the total R&D elasticity. The lag effects are higher than have previously been found for the 1970s data. We would like to thank Chris Bollinger, Bronwyn Hall and Paula Stephan for useful comments on the previous version of the paper. Earlier versions were presented at the 11th International Conference on Panel Data, Texas A&M University, the Midwest Econometrics Group Meeting, and the Annual Conference of the Southern Economic Association.  相似文献   
999.
The aim of this article is to construct a European production frontier using deterministic methods, and to break down growth and convergence during the period 1980–2001. The results show that EU growth is primarily driven by physical and human capital accumulation, the contribution of which is essential for the cohesion of European countries. We find capital accumulation and efficiency change to be important convergence factors within the EU, while technical change has worked against it. The approach used has also enabled us to analyze the differences in growth performance of Member States and highlight the role of human and public capital, supporting the European cohesion and development policies carried out in this period.  相似文献   
1000.
In this paper we estimate a standard version of the New Keynesian Monetary (NKM) model augmented with term structure in order to analyze two issues. First, we analyze the effect of introducing an explicit term structure channel in the NKM model on the estimated parameter values of the model, with special emphasis on the interest rate smoothing parameter using data for the Eurozone. Second, we study the ability of the model to reproduce some stylized facts such as highly persistent dynamics, the weak comovement between economic activity and inflation, and the positive, strong comovement between interest rates observed in actual Eurozone data. The Sect. 3 implemented is a classical structural method based on the indirect inference principle. We are grateful to Eduardo Ley, two anonymous referees and seminar participants at the XXXI Simposio de Análisis Económico (Oviedo, Spain) and Bank of Spain for their useful comments. Financial support from Ministerio de Ciencia y Tecnología and Universidad del País Vasco (Spain) and Fundación Séneca through projects SEJ2004-04811/ECON, 9/UPV00035.321-13511/2001 and I02937/PHCS/05, respectively, is gratefully acknowledged. The first author also thanks Fundación Ramón Areces for financial support.  相似文献   
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