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排序方式: 共有1309条查询结果,搜索用时 31 毫秒
1.
This paper reviews the changes in Shuanghui’s operations after the Smithfield acquisition as well as transformations in China’s pork industries. As income grows and diets change, there has been an increasing demand for high-quality pork and more processed pork products. However, China’s swine and pork industries are still at an early stage of development as evidenced by the low market concentration, intensive use of labour, a proliferation of intermediaries, and low levels of technology. Bounded by the established consumer preferences for freshness and the status quo in the midstream and upstream segments, Shuanghui is in a slow process of upgrading its domestic operations with Smithfield’s leading brands, import of chilled and frozen pork, advanced technologies, and the vertically integrated business model after this acquisition. In particular, it remains unclear whether Shuanghui can follow Smithfield’s experience to establish stable and safe hog supplies by multiplying self-owned hog farms, maintain and expand its current contracts with large-scale commercial hog farms, or rely more on global sourcing of pork primarily from the U.S.  相似文献   
2.
Upgrading in global value chains (GVCs) is an important path for developing countries to move along to capture higher benefits. Several qualitative studies of GVCs have identified two main upgrading types: economic (product, process, functional, and inter-sectoral) and social upgrading. The upgrading concept is widespread in productive sectors such as processed food, which has become a key export for developing countries. However, they have confronted multiple product standards required by global buyers. This study uses a case study of Thailand’s processed food exports (TPFEs). Although Thailand is a leading exporter of processed food, the country needs to upgrade in many areas related to production to meet global product standards and requirements. If Thailand fails to comply with global product standards, it will lose its export competitiveness. This study uses a gravity model to evaluate the impact of economic and social upgrading (EUP and SUP) on TPFEs. Our results show that upgrading types are significant in TPFEs, particularly for exports to developed countries. Process upgrading has a negative impact on TPFEs because of increased production costs to comply with product standards. However, process upgrading can lead to increased producers’ and exporters’ knowledge about how to comply with international standards. Consequently, process upgrading exhibits a lagged positive effect on TPFEs.  相似文献   
3.
This paper explores the importance of incorporating the financial leverage effect in the stochastic volatility models when pricing options. For the illustrative purpose, we first conduct the simulation experiment by using the Markov Chain Monte Carlo (MCMC) sampling method. We then make an empirical analysis by applying the volatility models to the real return data of the Hang Seng index during the period from January 1, 2013 to December 31, 2017. Our results highlight the accuracy of the stochastic volatility models with leverage in option pricing when leverage is high. In addition, the leverage effect becomes more significant as the maturity of options increases. Moreover, leverage affects the pricing of in-the-money options more than that of at-the-money and out-of-money options. Our study is therefore useful for both asset pricing and portfolio investment in the Hong Kong market where volatility is an inherent nature of the economy.  相似文献   
4.
Important changes have happened to the upstream segment of the coffee sector in Ethiopia - Africa’s biggest - in the last decade, as illustrated by the increasing adoption of improved production, harvest, and post-harvest practices. Upstream marketing has also improved and there have been large investments in processing capacity, shown by the extended coverage of wet mills. These improved practices are shown to be associated with positive impacts on coffee productivity and prices. Changes appear to be linked with multiple factors including local market reform, greater presence of public extension agents, high international prices, and a push for certification by international buyers. On the other hand, a combination of production (lack of improved seedlings, weather and disease shocks) as well as institutional issues (saving constraints and lack of vertical integration and traceability) have seemingly impeded more widespread uptake of improved practices and therefore better farm performance. The study illustrates the significant complexity in obtaining transformation at the farm level in these settings.  相似文献   
5.
This paper provides empirical evidence on the linkage between foreign exchange market volatility and daily 90-day covered interest rate parity (CIP) conditions of the three major exchange rates against the US dollar (US$). Markov regime shifting models were utilized to generate time series of volatility regime probabilities and these were used to explain the first and second moments of the daily deviations from and the transaction cost bands around the covered parity conditions. We find a significant positive relationship between the deviations and the regime probabilities, indicating an increasing probability of higher volatility state being associated with rising deviations (both first and second moments) from the parity condition. Similar positive relationship is found for the transaction bands. Rising (falling) probabilities of high (low) volatility regimes increased the first and second moments of the bands. Furthermore, we find a higher volatility state combined with a US$ depreciation is associated with significantly higher volatility in the daily deviations than an appreciation. Also, US$ depreciation is associated with widening transaction bands. This suggests that the level of market uncertainty was higher when the US$ was depreciating.  相似文献   
6.
The main objective of this paper is to use the Markov regime‐switching modelling framework to describe and analyse the credibility of a number of countries participating in the European Monetary System during 1980–1998. Our credibility indicator, based on Hughes Hallet et al.'s (1997) methodology, is subject to discrete regime shifts and is made dependent on macroeconomic fundamentals. We carry out extensive testing to assess the specification of the Markov regime‐switching model and the potential existence of permanent breaks. A contribution of our paper is the specification of a multivariate Markov switching model that allows us to examine whether macroeconomic variables have asymmetric effects on credibility. Another contribution is the specification of a regime‐switching model with time‐varying transition probabilities, which enables us to determine whether changes in macroeconomic variables can trigger switches between the low and high credibility regimes. We find strong evidence of regime switching behaviour in all countries. Both the level of credibility and the transition probabilities display an asymmetric response to changes in macroeconomic variables, with the stance of fiscal policy exerting the most systematic influence in all countries.  相似文献   
7.
UNEMPLOYMENT, HYSTERESIS AND TRANSITION   总被引:3,自引:0,他引:3  
In this paper, we quantify the degree of persistence in the unemployment rates of transition countries using a variety of methods benchmarked against the EU. Initially, we work with the concept of linear ‘Hysteresis’ as described by the presence of unit roots in unemployment as in most empirical research on this area. Given that this is potentially a narrow definition, we also take into account the existence of structural breaks and nonlinear dynamics in unemployment. Finally, we examine whether CEECs' unemployment presents features of multiple equilibria, that is, if it remains locked into a new level whenever some structural change or sufficiently large shock occurs. Our findings show that, in general, we can reject the unit‐root hypothesis after controlling for structural changes and business‐cycle effects, but we can observe the presence of a high and low unemployment equilibria. The speed of adjustment is faster for CEECs than the EU, although CEECs tend to move more frequently between equilibria.  相似文献   
8.
Developments in the recent past have substantially increased our ability to measure, compute, and communicate. We take the view that a corresponding improved understanding of processes in the life sciences will come about only through more intensive studies of properties of statistical methods and algorithms and transparent, open source computing environments.  相似文献   
9.
QUADRATIC TERM STRUCTURE MODELS FOR RISK-FREE AND DEFAULTABLE RATES   总被引:4,自引:0,他引:4  
In this paper, quadratic term structure models (QTSMs) are analyzed and characterized in a general Markovian setting. The primary motivation for this work is to find a useful extension of the traditional QTSM, which is based on an Ornstein–Uhlenbeck (OU) state process, while maintaining the analytical tractability of the model. To accomplish this, the class of quadratic processes, consisting of those Markov state processes that yield QTSM, is introduced. The main result states that OU processes are the only conservative quadratic processes. In general, however, a quadratic potential can be added to allow QTSMs to model default risk. It is further shown that the exponent functions that are inherent in the definition of the quadratic property can be determined by a system of Riccati equations with a unique admissible parameter set. The implications of these results for modeling the term structure of risk-free and defaultable rates are discussed.  相似文献   
10.
纽约股票市场对中国A股市场的影响   总被引:3,自引:0,他引:3  
首先,本文考察了纽约股市波动对中国A股市场的影响。一般认为,中国的A股市场由于严格的资本控制而免受外国影响。但是,通过月度、每周、每日的样本数据(1992年到2004年),经过季节性调整和汇率变动调整后,我们发现上海和深圳A股市场的变动与美国股票价格指数变动相一致。其次,我们考察国家贝塔值(country beta)在马尔可夫转换误差修正模型中的动态关系。对中国市场来说,国家贝塔值和错误纠正项的重要性紧密相连。在东亚金融危机之前,美国市场对中国A股市场的影响普遍存在,而东亚金融危机产生后,则是通过国家贝塔值来影响中国股市的收益。  相似文献   
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