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121.
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This paper concerns a procedure jor measuring the major economic risks and returns involved in forage production. Conventional static production economics was modified to permit the use of decision criteria under conditions of weather risk. Twenty-six years of rainfall data were analyzed to determine the expected mean number of days available for fieldwork ivithin each of three specified seasons. These seasons correspond with three critical forage production periods: e.g., (1) land preparation and planting, (2) hay harvest, and (3) corn silage harvest and fall plouiing. A probability distribution of days available for field operations was derived, and the number of days available in any one year was randomly selected from this distribution. Given the acreage involved and the machinery system, the days required to perform nine specified field operations were calculated. If the number of days required within a specified season exceeded the number of days available, the value of the crops produced was reduced by a set of yield reducing functions for each deficient day. Overhead and use-associated machinery costs uiere calculated, and net returns over machinery costs were determined for five machinery systems at 75,150, 225, and 300 acres. Cette publication montre une façon de mesurer les plus grands risques économiques et les profits provenant de la production fourragére. On a modifyé?économie de production conventionnelle et statique afin de tenir compte des critéres de décision utilisés sous les conditions de risques climatologiques. Les chutes de pluie ont été analysées sur une période de vingt-six ans afin de determiner la moyenne des jours disponibles au travail des champs, et ce, pour chacune des trois saisons specifiées. Ces saisons correspondent aux trois périodes critiques de la production fourragere: (1) la préparation du sol et le semis, (2) la récolte du foin, et (3) la récolte du maïs à ensiler et les labours ?automne. On a calculé la distribution probable des jours disponibles pour les travaux des champs et, de cette distribution, le nombre des jours disponibles fut choisi au hasard dans une quel-conque année. Selon une superfécie et un systéme dé machinerie determineés, le nombre de jours nécessaires à?exécution de neuf operations differéntes fut calculé. Lorsque le nombre de jour requis pour ?exécution des travaux ?une saison donnee dépasse le nombre de jours disponibles, la valeur des récoltes produites est réduite par une diminution de rende-ment de plusieurs facteurs, une diminution fonction du nombre de jours manquants. Les frais géneraux et les dépenses associées à?utilisation de la machinerie furent calculés. Les profits nets sur les dépenses de machinerie ont été déterminés pour chaque systéme ?equipement avec 75, 150, 225, et 300 âcres.  相似文献   
124.
The oil and gas industry is subject to different types of risks, many of which have the potential to generate extreme results. Classifying extreme events as global, industry specific and firm specific, we use a Bayesian probability model and the Exponential Generalized Autoregressive Conditional Heteroskedasticity (EGARCH) model to evaluate the impact of disclosure of extreme events on returns and return volatilities. The results suggest political events have more of a pronounced effect compared to those classified as economic events. The overall effects are more pronounced at the global and firm‐level classifications. At the firm level, extreme economic events have a more significant impact than political extreme events.  相似文献   
125.
Mangrove ecosystems are rapidly declining in many parts of the world. This has resulted in the loss of important environmental and economic products and services including forest products, flood mitigation and nursery grounds for fish. The aquaculture industry was the single biggest threat to mangroves in the Philippines until 1981 when conversion of the remaining mangrove stands was prohibited by law. However, the decreasing yield from capture fisheries is putting pressure for the re-examination of this policy. To understand the importance of mangroves, insight is needed into the value of products and services provided is needed. This article compares the costs and benefits of mangrove preservation with those generated by alternative uses such as aquaculture and forestry. Equity and sustainability objectives are taken into account, in addition to economic efficiency and analyzed according to the perspectives of the different types of decision makers involved.  相似文献   
126.
This study implements a regular vine copula methodology to evaluate the level of contagion among the exchange rates of six Latin American countries (Argentina, Brazil, Chile, Colombia, Mexico, and Peru) from June 2005 to April 2012. We measure contagion in terms of tail dependence coefficients, following Fratzscher's (1999) definition of contagion as interdependence. Our results indicate that these countries are divided into two blocks. The first block consists of Brazil, Colombia, Chile, and Mexico, whose exchange rates exhibit the largest dependence coefficients, and the second block consists of Argentina and Peru, whose exchange rate dependence coefficients with other Latin American countries are low. We also found that most of the Latin American exchange rate pairs exhibit asymmetric behaviors characterized by nonsignificant upper tail dependence and significant lower tail dependence. These results imply that there exists contagion in Latin American exchange rates in periods of large appreciations, whereas there is no evidence of contagion during periods of currency depreciation. This empirical regularity may reflect the “fear of appreciation” in emerging economies identified by Levy‐Yeyati, Sturzenegger, and Gluzmann (2013). (JEL C32, C51, E42)  相似文献   
127.
For many decades the US dollar has remained unchallenged as the world’s dominant international currency. What is behind its persistent pre-eminence in the international monetary system and can this be expected to last? Could the euro rival or even surpass the dollar as the leading currency? If it did, what would be the consequences for Euroland?   相似文献   
128.
This work intends to present chaos theory (and dynamical systems such as the theories of complexity), in terms of interpretation of ecological phenomena. The chaos theory applied in the context of ecological systems, especially in the context of fisheries has allowed the recognition of the relevance of this kind of theories to explain fishing phenomena and fisheries policies. It has permitted new advances in the study of marine systems, contributing to the preservation of fish stocks. This paper deals with the way how to manage fisheries taking chaos in account of the problem.  相似文献   
129.
After a report of results about infinite servers queues, essentially on its busy period, a model is built, using networks of queues with infinite servers in each node, to study a two echelons repair system for example of a fleet of aircraft, shipping or trucks. The customers are the failures, and their service time is the time that goes from the instant at which they occur till they are completely repaired. The failing repairs occur in a base or in a remote station. The whole failures detected in the base are repaired there. Some of the failures detected in the station are repaired there and the others in the base. The results referred above allow the determination of a two echelons repair system performance measures. In this application, models of Carrillo (1991) and Ferreira (1996) are considered, improved and completed. The theory is illustrated with a numerical example.  相似文献   
130.
The historical study of the Spanish nineteenth-century banking system has been almost exclusively carried out through a consideration of the experiences of the joint-stock banks. But the very scarce number of these, and their territorial distribution, makes it necessary for us to look for other financial intermediaries who were able to satisfy the demand for banking services in that time and place. We demonstrate that this role was fulfilled by the banking merchants and banking houses operating through individual firms and partnerships. The object of this work is to make their activities better known and vindicate their importance. The sources used for the study are mainly the accounting documents of several banking houses.  相似文献   
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