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21.
Using high-frequency data for major volatility indexes, we compute the volatility of volatility and show that its logarithm follows a fractional Brownian motion with Hurst parameter smaller than 1/2 thereby extending to the volatility asset class the recent findings obtained for the equity index markets. The results confirm that the volatility of volatility is a rough process and it possesses the long memory property. We also show that the correlation between the volatility and the volatility of volatility is positive, consistent with observations in the volatility option market. Lastly, a robustness check using volatility futures confirms the findings.  相似文献   
22.
We analyse the heterogeneity in firms’ decisions to engage in R&D cooperation, taking into account the type of partner (competitors, suppliers or customers, and research institutions) and the sector to which the firm belongs (manufactures or services). We use information from the Technological Innovation Panel (PITEC) for Spanish firms and estimate multivariate probit models corrected for endogeneity which explicitly consider the interrelations between the different R&D cooperation strategies. We find that placing a higher importance to publicly available information (incoming spillovers), receiving public funding and firm size increase the probability of cooperation with all kind of partners but the role is much stronger in the case of cooperative agreements with research institutions and universities. Our results also suggest that R&D intensity and the importance attributed to the lack of qualified personnel as a factor hampering innovation are key factors influencing positively R&D cooperation activities in the service sector but not in manufactures.  相似文献   
23.
Objective: To estimate the economic burden of hypoglycemia on the healthcare system at the national level in the US between the years of 2005–2009.

Methods: This study analyzed the National Hospital Ambulatory Medical Care Survey (NHAMCS), including emergency department (ED) and outpatient department (OPD) components, and the National Ambulatory Medical Care Survey (NAMCS). The annual rates of ED and OPD visits associated with hypoglycemia were reported. Subsequent medical services after disposition were studied. The unit cost of specific medical service was estimated from the Medical Expenditure Panel Survey (MEPS). All annualized costs were adjusted to US 2009 dollars. We also estimated the rates of injury and ambulance use incurring within a visit for hypoglycemia.

Results: The total direct medical cost of hypoglycemia was estimated as $3.49 billion in 2005 and decreased gradually to $1.84 billion in 2009. The declining trend was correlated with hospital admissions from ED, which decreased from 170 665 in 2005 to 71,751 in 2009. Consequently, the estimated annual expenditure of hospitalization for hypoglycemia from ED declined over time by more than half ($2.90 billion in 2005, $1.25 billion in 2009). Injury was reported among 9.5% of the ED visits for hypoglycemia. Ambulances were used among 58% of the ED visits for hypoglycemia.

Conclusion: Hypoglycemia poses a significant burden on the healthcare system; however, annual direct medical cost of severe hypoglycemia in the US decreased over the 5 years studied, which is attributable to tremendous decrease in need of hospitalization following an ED visit.  相似文献   

24.
The paper deals with optimal portfolio choice problems when risk levels are given by coherent risk measures, expectation bounded risk measures or general deviations. Both static and dynamic pricing models may be involved. Unbounded problems are characterized by new notions such as (strong) compatibility between prices and risks. Surprisingly, the lack of bounded optimal risk and/or return levels arises for important pricing models (Black and Scholes) and risk measures (VaR, CVaR, absolute deviation, etc.). Bounded problems present a Market Price of Risk and generate a pair of benchmarks. From these benchmarks we introduce APT and CAPM-like analyses, in the sense that the level of correlation between every available security and some economic factors explains the security expected return. The risk level non correlated with these factors has no influence on any return, despite the fact that we are dealing with risk functions beyond the standard deviation.  相似文献   
25.
Commerical bank debts of developing countries are held by large international banks and smaller domestic banks. This paper investigates how debt concentration—the proportion of a country's debt held by large banks relative to small banks—affects the secondary market price for these loans. We find that countries with higher concentrations have higher secondary-market prices. We explain this empirical finding in a bargaining model that endogenizes the maximum penalty that banks can credibly impose on a recalcitrant debtor. We show that the banks' bargaining power increases with the degree of debt concentration, thus increasing repayment and secondary-market prices.  相似文献   
26.
27.
This article aims at contributing to a body of work about children and families by exploring the importance of socio‐economic context and social capital for understanding the ways in which money is perceived, obtained and used by children. Alleged contrasts in terms of money management, consumption priorities and postponement of gratification, especially among middle and working classes, have already been debated. It seems thus relevant to investigate if these presumable contrasts apply to children and why. Do children from different socio‐economic contexts reveal the traits that have been attributed to their households? To this end, a mixed methods research project was developed involving 245 children attending different primary schools in Portugal—one private school targeted at upper class children and one state‐sponsored school located in a working‐class area. The results revealed significant differences by school and household typology.  相似文献   
28.
Research analysing the antecedents of a firm’s absorptive capacity suggests that transformational leadership (TL) is one of its main determinants. However, the few studies focusing on the relationship between these two variables do not explicitly assess why transformational leaders facilitate knowledge acquisition, sharing and retention inside firms. This paper suggests that the reason is that the former contributes to the creation of an organisational context that favours learning processes. We test our research model on a sample of 467 Spanish industrial firms. Findings provide evidence that TL is positively related to the firm’s absorptive capacity and that this relationship is mediated by some organisational learning facilitators: experimentation, risk-taking, interacting with external environment and dialogue.  相似文献   
29.
An important issue today is the compatibility of agricultural frontiers, which are driven by economic objectives, with conservationist views. In the Amazon, family farmers are concerned with this issue since they are at the same time actors of the agricultural frontier and considered as potential actors of the preservation of the forest. Through the study of a highly symbolic settlement project in the State of Pará, this paper focuses on the role that family farmers can play in meeting sustainability goals. The central argument which is developed in this paper is that this objective may be achieved when projects do not presuppose social and spatial relationships; rather, it advocates an approach which is attentive to place-making processes.  相似文献   
30.
Abstract

The relationship between tourism and climate change is reciprocal. The effects of climate change on tourism are undeniable. However, tourism and climate change are complex and cross-cutting phenomena that enter policy agendas at different moments and with different discourses. This paper analyses the coherence between the policy domains of climate and tourism at the formulation stage of the policy process, focusing on national and regional government levels and the key touristic offer in Spain – that of sun, sea and sand. The proposed method analyses three dimensions within policy documents: frame significance, policy scope and connotation. Results reveal the imbalance between the two policy domains; the lack of concrete actions and stable mechanisms for achieving greater coherence; and the different conceptions of the issue. The paper considers the causal relationships between tourism and climate change, the consequences of mutual impacts, and the temporal dimension of problem framing. This research brings together three fields of knowledge – tourism, climate change and public policies – and suggests enhancing coherence between tourism and climate policies in order to address the sustainability of tourism destinations.  相似文献   
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