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961.
This article analyses co‐movements in a wide group of commodity prices during the time period 1992–2010. Our methodological approach is based on the correlation matrix and the networks inside. Through this approach we are able to summarize global interaction and interdependence, capturing the existing heterogeneity in the degrees of synchronization between commodity prices. Our results produce two main findings: (a) we do not observe a persistent increase in the degree of co‐movement of the commodity prices in our time sample, however from mid‐2008 to the end of 2009 co‐movements almost doubled when compared with the average correlation; (b) we observe three groups of commodities which have exhibited similar price dynamics (metals, oil and grains, and oilseeds) and which have increased their degree of co‐movement during the sampled period.  相似文献   
962.
This paper explores farmers’ willingness to adopt genetically modified (GM) oilseed rape prior to its commercial release and estimates the ‘demand’ for the new technology. The analysis is based upon choice experiments with 202 German arable farmers. A multinomial probit estimation reveals that GM attributes such as gross margin, expected liability from cross pollination, or flexibility in returning to conventional oilseed rape significantly affect the likelihood of adoption. Neighbouring farmers’ attitudes towards GM cropping and a number of farmer and farm characteristics were also found to be significant determinants of prospective adoption. Demand simulations suggest that adoption rates are very sensitive to the profit difference between GM and non‐GM rape varieties. A monopolistic seed price would substantially reduce demand for the new technology. A monopolistic seed supplier would reap between 45% and 80% of the GM rent, and the deadweight loss of the monopoly would range between 15% and 30% of that rent. The remaining rent for farmers may be too small to outweigh possible producer price discounts resulting from the costs of segregating GM and non‐GM oilseed rape along the supply chain.  相似文献   
963.
Determinants of herbicide use in rice production in the Philippines   总被引:1,自引:0,他引:1  
This study identifies farm‐specific and market factors affecting the adoption of herbicides and the level of herbicide use by rice farmers in the Philippines. This requires the application of a modified version of Heckman's two‐step method to estimate a random‐effects double‐hurdle model for unbalanced panel data. The age of the farmer, household size, and irrigation use are significant determinants of the decision of farmers to adopt herbicides as an alternative to manual weeding, while economic variables such as the price of herbicides, total income, and access to credit determine the level of herbicide use. Determinants of both adoption and level are land ownership, farm area, and the method of crop establishment. These results are potentially relevant when designing policies to reduce excessive herbicide use or to encourage the adoption of alternative weed control methods such as integrated weed management.  相似文献   
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967.
One aspect of reforming the world monetary system is the issue of designing a set of ‘rules of the game’ within which countries can pursue their own national objectives and yet which still leads to some form of global coordination of macroeconomic policies. The issue of strategic interactions between countries has recently received some analytical insights with the application of game theory to the economics literature on interdependence between countries. The purpose of this paper is to survey these recent applications of static and dynamic game theory to the question of international policy coordination. It also surveys the results of the few empirical attempts to measure the potential gains to coordination.  相似文献   
968.
In this paper we offer a definition of a country "debt crisis" based upon the amount of new borrowing relative to the cost of servicing past debt. Policy implications for both debtor countries and their creditors are examined. An empirical application is made to Latin American countries, 1978–82. The causes of the debt problems created during this period are investigated with respect to the extent they were the result of rising interest rates vis à vis increased borrowing.  相似文献   
969.
Summary In this paper we consider Anonymous Sequential Games with Aggregate Uncertainty. We prove existence of equilibrium when there is a general state space representing aggregate uncertainty. When the economy is stationary and the underlying process governing aggregate uncertainty Markov, we provide Markov representations of the equilibria.Table of notation Agents' characteristics space ( ) - A Action space of each agent (aA) - Y Y = x A - Aggregate distribution on agents' characteristics - (X) Space of probability measures onX - C(X) Space of continuous functions onX - X Family of Borel sets ofX - State space of aggregate uncertainty ( ) - x t=1 aggregate uncertainty for the infinite game - = (1,2,...,t,...) - t t (1, 2,..., t) - L1(t,C ×A),v t Normed space of measurable functions from t toC( x A) - 8o(t,( x A)) Space of measurable functions from tto( x A) - Xt Xt= x s=1 t X - X t Borel field onX t - v Distribution on - vt Marginal distribution of v on t - v(t)((¦t)) Conditional distribution on given t - vt(s)(vts)) Conditional distribution on t given s (wheres) - t Periodt distributional strategy - Distributional strategy for all periods =(1,2,...,t,...) - t Transition process for agents' types - ( t,t,y)(P t+1(, t , t ,y)) Transition function associated with t - u t Utility function - V t (, a, , t) Value function for each collection (, a, , t ) - W t (, , t ) Value function given optimal action a - C() Consistency correspondence. Distributions consistent with and characteristics transition functions - B() Best response correspondence (which also satisfy consistency) - E Set of equilibrium distributional strategies - x t=1 ( t , (x A)) - S Expanded state space for Markov construction - (, a, ) Value function for Markov construction - P( t * , t y)(P(, t * , t , y )) Invariant characteristics transition function for Markov game We wish to acknowledge very helpful conversations with C. d'Aspremont, B. Lipman, A. McLennan and J-F. Mertens. The financial support of the SSHRCC and the ARC at Queen's University is gratefully acknowledged. This paper was begun while the first author visited CORE. The financial support of CORE and the excellent research environment is gratefully acknowledged. The usual disclaimer applies.  相似文献   
970.
The damage costs of climate change toward more comprehensive calculations   总被引:2,自引:2,他引:2  
It is argued that estimating the damage costs of a certain benchmark climate change is not sufficient. What is needed are cost functions and confidence intervals. Although these are contained in the integrated models and their technical manuals, this paper brings them into the open in order to stimulate discussion. After briefly reviewing the benchmark climate change damage costs, region-specific cost functions are presented which distinguish tangible from intangible losses and the losses due to a changing climate from those due to a changed climate. Furthermore, cost functions are assumed to be quadratic, as an approximation of the unknown but presumably convex functions. Results from the damage module of the integrated climate economy modelFUND are presented. Next, uncertainties are incorporated and expected damages are calculated. It is shown that because of convex loss functions and right-skewed uncertainties, the risk premium is substantial, calling for more action than analysis based on best-guess estimates. The final section explores some needs for further scientific research.  相似文献   
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