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241.
The aim of this paper is to analyze the economic and social cohesion in the European Union. There are different factors to explain the convergence process and besides, empirical findings are not conclusive. To the European Union, GDP per head interregional differences have decreased for certain periods but it has remained unchanged or even increased for others periods. The second report on the economic and social cohesion indicates that some decades are necessary to eliminate regional differences. These differences in regional GDP are mainly explained by differences in their productive structures, degree of innovate activity, communications structures, which depend on the relative level of transport infrastructures, and manpower qualifications. This analysis allows us to obtain some conclusions to the economic policies and the social cohesion. A preliminary version of this paper was presented in the 57th International Atlantic Conference, held in Lisbon, Portugal, March 10–14, 2004.  相似文献   
242.
In this article, we show that macroeconomic time series may contain unit and fractional roots at both, at zero and at zero and at the seasonal frequencies. The importance of the root at the long run or zero frequency requires in many cases to consider this root at both, separately in an independent polynomial, and also included in the seasonal one. Several Monte Carlo experiments are conducted to examine cases when the root at the zero frequency is not appropriately considered. An empirical application based on the tests of Robinson, Peter M. “Efficient Tests of Nonstationary Hypotheses,” Journal of the American Statistical Association, 89, 1994, pp. 1420–37 is also carried out at the end of the article.The author gratefully acknowledges financial support from the Government of Navarra (“Ayudas de Formación e Investigación y Desarrollo”).  相似文献   
243.
244.
Unilateral abatement is sometimes advocated in order to set a good example that will make other countries follow. The aim of this paper is to investigate whether existence of correlated cost uncertainty provides an incentive for a country to undertake unilateral abatement. The theoretical model is driven by two main mechanisms; first, a learning effect, as the follower country might reduce its risk premium as it can observe the cost level in the leader country. Second, there is the public good effect, i.e., the marginal benefit of abatement declines when abatement is a public good and other countries contribute to pollution reductions. Results shows that unilateral abatement would be efficient in reducing uncertainty about the unit costs of abatement if a country with low cost uncertainty would undertake abatement first, while a country with initially high cost uncertainty would follow. However, countries may prefer to act simultaneously because of the larger uncertainties that are inherent in a sequential game.   相似文献   
245.
This paper presents an agent-based simulation model with local network externality to analyze strategic interactions over investment on new economic knowledge. R&D knowledge flows and spillovers are the results of non-cooperative games played between neighboring agents in the model. The model demonstrates a situation where no agents have incentives to hide their economic knowledge, a situation that is observed in open source software development projects. The likelihood of obtaining a stable situation where new economic knowledge is openly shared is increased when heterogeneity of agents is introduced.   相似文献   
246.
Abstract

Background and aims: A wide range of treatment options are available for hepatocellular carcinoma (HCC), including systemic treatment with tyrosine kinase inhibitors (TKIs) such as sorafenib and lenvatinib, immunotherapies, locoregional therapies such as selective internal radiation therapy (SIRT) and treatments with curative intent such as resection, radiofrequency ablation and liver transplantation. Given the substantial economic burden associated with HCC treatment, the aim of the present analysis was to establish the cost of using SIRT with SIR-Spheres yttrium-90 (Y-90) resin microspheres versus TKIs from healthcare payer perspectives in France, Italy, Spain and the United Kingdom (UK).

Methods: A cost model was developed to capture the costs of initial systemic treatment with sorafenib (95%) or lenvatinib (5%) versus SIRT in patients with HCC in Barcelona Clinic Liver Cancer (BCLC) stages B and C. A nested Markov model was utilized to model transitions between progression-free survival (PFS), progression and death, in addition to transitions between subsequent treatment lines. Cost and resource use data were identified from published sources in each of the four countries.

Results: Relative to TKIs, SIRT with SIR-Spheres Y-90 resin microspheres were found to be cost saving in all four country settings, with the additional costs of the microspheres and the SIRT procedure being more than offset by reductions in drug and drug administration costs, and treatment of adverse events. Across the four country settings, total cost savings with SIR-Spheres Y-90 resin microspheres fell within the range 5.4–24.9% and SIRT resulted in more patients ultimately receiving treatments with curative intent (4.6 vs. 1.4% of eligible patients).

Conclusion: SIR-Spheres Y-90 resin microspheres resulted in cost savings relative to TKIs in the treatment of unresectable HCC in all four country settings, while increasing the proportion of patients who become eligible for treatments with curative intent.  相似文献   
247.
A bandit problem consisting of a sequence of n choices (n) from a number of infinitely many Bernoulli arms is considered. The parameters of Bernoulli arms are independent and identically distributed random variables from a common distribution F on the interval [0,1] and F is continuous with F(0)=0 and F(1)=1. The goal is to investigate the asymptotic expected failure rates of k-failure strategies, and obtain a lower bound for the expected failure proportion over all strategies presented in Berry et al. (1997). We show that the asymptotic expected failure rates of k-failure strategies when 0<b1 and a lower bound can be evaluated if the limit of the ratio F(1)–F(t) versus (1–t)b exists as t1 for some b>0.  相似文献   
248.
Simple models of local government behavior predict equal effects of private income and unconditional federal grants on local government expenditures. Numerous empirical analyses, however, find that the effect of grants is larger than the income effect. We argue that this flypaper effect may be a result of weak political leaderships in multi–issue and multi–party decision–making environments. In multi–issue institutions, a strong political leadership may reduce inefficiency due to interest group influence and inter–party bargaining in the local council. Utilizing data for Norwegian local governments in the 1930s, we find that political strength reduces the size of the flypaper effect. When the local council consists of only one political party, we cannot reject absence of a flypaper effect, while the flypaper effect is large in fragmented local councils. Received: June 2000 / accepted: February 2001  相似文献   
249.
Action Research is Similar to Design Science   总被引:2,自引:0,他引:2  
In management information systems (MIS) action research is long considered as promising but low-level research approach. It has an utmost relevance because action researchers are working with practitioners to solve the important practical problem. Design science outlined some years ago is just winning a wider audience. Action research was traditionally classified into qualitative research methods. But it seems to be the “wrong” home of action research. We shall show that after comparison of the seven aspects: concrete results of the study, knowledge produced, activities, the intent and the nature of a study, the division of labor in a study and generation, use and test of knowledge, the concordance between the characteristics of action research on the one hand and of design science on the other hand is very good. Hence, action research and design science should next be considered as similar research approaches, and this is a turning point in the history of both action research and design science.  相似文献   
250.
Erhard Cramer  Udo Kamps 《Metrika》2003,58(3):293-310
Expressions for marginal distribution functions of sequential order statistics and generalized order statistics are presented without any restrictions imposed on the model parameters. The results are related to the relevation transform, to the distribution of the product of Beta distributed random variables, and to Meijers G-functions. Some selected applications in the areas of moments, conditional distributions, recurrence relations, and reliability properties are shown. Key words:Order statistics; Generalized order statistics; Sequential order statistics; Record values; Distribution theory; Meijers G-function; Recurrence relations; Reliability properties.  相似文献   
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