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81.
In this article, we take account of an evaluation of the short- and medium-term effects of the transmission mechanism of fiscal policy in EU and OECD countries and their dependence on the state of the economy and fiscal behaviour. Our findings indicate that (i) across EU member states the impact of government spending on economic performance is larger in the accession than in core member states, (ii) since the onset of the economic/financial crisis the government spending multipliers have become larger in both core and accession EU member states, and (iii) a comparison with fiscal responses in the OECD countries shows robustness of our estimates. The conclusion implies that the austerity measures present a substantial drag for economic activity in accession EU countries. Thus, we may state that not considering the fiscal behaviour and state of the economy gives misleading fiscal multiplier effects, which in turn lead to the adoption of inappropriate fiscal measures that even worsen a country's economic situation.  相似文献   
82.
Recent non-parametric statistical analysis of high-frequency VIX data (Todorov and Tauchen, 2011) reveals that VIX dynamics is a pure jump semimartingale with infinite jump activity and infinite variation. To our best knowledge, existing models in the literature for pricing and hedging VIX derivatives do not have these features. This paper fills this gap by developing a novel class of parsimonious pure jump models with such features for VIX based on the additive time change technique proposed in Li et al., 2016a, Li et al., 2016b. We time change the 3/2 diffusion by a class of additive subordinators with infinite activity, yielding pure jump Markov semimartingales with infinite activity and infinite variation. These processes have time and state dependent jumps that are mean reverting and are able to capture stylized features of VIX. Our models take the initial term structure of VIX futures as input and are analytically tractable for pricing VIX futures and European options via eigenfunction expansions. Through calibration exercises, we show that our model is able to achieve excellent fit for the VIX implied volatility surface which typically exhibits very steep skews. Comparison to two other models in terms of calibration reveals that our model performs better both in-sample and out-of-sample. We explain the ability of our model to fit the volatility surface by evaluating the matching of moments implied from market VIX option prices. To hedge VIX options, we develop a dynamic strategy which minimizes instantaneous jump risk at each rebalancing time while controlling transaction cost. Its effectiveness is demonstrated through a simulation study on hedging Bermudan style VIX options.  相似文献   
83.
Desertification and land degradation are worldwide problems affecting soil, vegetation and the livelihoods of rural populations. Bowal (plural bowé) is a particular form of degraded land that occurs in tropical regions and leads to the exposure of ferricretes, which are unsuitable for farming. Bowé are more common on farmland and degraded savanna. Changes in land use/land cover were used to map a region of 6.7 million ha in northern Benin, West Africa in 1975, 1990 and 2010. The changes observed during these periods (1975–1990, 1990–2010 and 1975–2010) were used to predict the occurrence of bowé in the period up to 2050 using Markovian chain analysis. The results showed a considerable change in land use/land cover during the three periods. The types of land on which bowé occur (farmland and degraded savanna) increased in northern Benin by 5.4% per year during the period 1975–1990 and 9.5% per year during the periods 1990–2010, while the natural vegetation (forest, woodland and tree savanna) decreased by the same amount. The future scenarios also predicted the same trend. In the period 1975–1990, 1.28 million ha (26%) of natural vegetation was converted to degraded savanna and farmland while 2.23 million ha (53%) of natural vegetation was converted to degraded savanna and farmland in the period 1990–2010. Based on the dynamics recorded during the period 1975–1990 and 1990–2010 respectively, a total of 1.28 million ha (26% of the natural vegetation that was present in 1975) and 1.29 million ha (31% of the natural vegetation that was present in 1990) will be converted to farmland and degraded savanna in the study area by 2050.Thus bowalization will persist and increase in the period up to 2050. The natural vegetation could disappear if protection and restoration measures are not taken. It is thus important to take measures to stop the degradation and to implement programs to restore soils on bowé based on the soil and water conservation techniques used on highly degraded West African soils, such as zaï pit and stone rows with grass strips. Some native plants species adapted to bowalization and resistant to climate change in northern Benin (e.g. Asparagus africanus, Andropogon pseudapricus and Combretum nigricans) should be used in association with soil and water conservation techniques on bowé.  相似文献   
84.
Forced to compete with private and public sector providers, charities experience tensions as the quest for a more commercially-oriented position may conflict with their social imperative. Little attention has been given to understanding the experiences of local charities as service providers. This paper captures the reactions of those working on the charity front line.  相似文献   
85.
Our research examines the benefits and drawbacks for cooperatives who participate in voluntary coffee certifications. We interviewed administrators at twenty Costa Rican coffee cooperatives about management practices related to voluntary certification. Voluntary certifications are popular among coffee cooperatives. Access to certified markets is facilitated by state support of the cooperative sector, regulation of the coffee sector and well-enforced environmental and social laws. However, there are no significant or consistent financial incentives for farmers to pursue certification. Multiple certifications may lower auditing and implementation costs, but cooperatives rarely receive the full premium for multiply-certified coffee. Low market demand for certified coffee, weak price incentives and high auditing and management costs encourage cooperatives to certify only a portion of their members. This strategy rewards compliant farmers rather than inducing widespread change to farming practices among the entire membership. Though financial incentives are weak, certifications offer non-financial benefits to both farmers and cooperatives, including better management and more resilient cooperatives.  相似文献   
86.
This paper uses a model of strategic interaction among firms –that set discriminatory and nonlinear prices– in addition to public information on prices of the plans marketed by the three major mobile phone companies, to assess the extent to which on-net/off-net price differentials in the plans they offered could represent predatory practices in the mobile telephony market in Chile. The results show that the largest companies offered a few plans with an off-net/on-net price differential larger than what a competitive theoretical model predicts. This larger differential is consistent with the notion of predation defined by Hoernig (2007) as reducing a competitor's profits. Despite the fact that these plans were a small fraction of all the plans mobile phone firms offered, they were recently banned by the antitrust authority because of their potential anticompetitive effects.  相似文献   
87.
In order to promote angel investments, attracting those who have entrepreneurial experience is necessary because their capital, unique managing experience, and business insight are highly beneficial to the performance of the investment. This can be accomplished by providing a preferred investment environment for potential angels who have entrepreneurial backgrounds. In this paper, we use an adaptive conjoint analysis to identify preferred investment environments represented as a combination of support policies for business angels who have entrepreneurial experience in Korea. Of particular interest is a preference for angel insurance. This insurance is newly proposed based on prospect theory, which explains that people tend to be more sensitive to a loss than to a gain. The value of the angel insurance is compared to those of tax policies and matching funds for business angels. The empirical results are expected to contribute to promoting angel investments by attracting entrepreneurs to become business angels.  相似文献   
88.
对与油气管道领域相关的ISO、API、ASME、ASTM、NACE 5所知名国外标准化组织进行了简要介绍,对各组织在提案申请要求、提案内容、尤其是标准制修订流程方面进行了初步对比分析,同时以参与国际标准化组织ISO,为例详细说明了参与国际标准的注意事项及技巧,最后提出了我国在油气管道领域开展标准国际化的启示和建议。  相似文献   
89.
The importance of board committees – specialized subgroups that exist to perform many of the board's most critical functions, such as setting executive compensation, identifying potential board members, and overseeing financial reporting – has grown over time due to increased legal requirements and greater complexity of the environment in which firms operate. This has resulted in a large body of work examining board committees across the accounting, finance, and management disciplines. However, this research has developed rather independently within each discipline, preventing scholars and practitioners from developing a comprehensive understanding of board committees. To address this issue, we conduct a comprehensive review of the literature that: 1) summarizes and synthesizes antecedents and outcomes associated with board committees in publicly‐traded firms in English common law countries; and 2) offers a critical analysis of existing research, providing recommendations for advancements and new directions in board committee research.  相似文献   
90.
随着计算机网络的飞速发展,OA系统已是高校信息化建设的重要标志。本文研究了高校信息化办公现状,针对存在的问题,设计并实现了基于B/S体系结构的协同办公系统。系统实现采用了MVC模式。经测试,系统满足设计需求,运行可靠。  相似文献   
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