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排序方式: 共有1007条查询结果,搜索用时 15 毫秒
41.
Using a new data set on Swiss cantons since 1890, we analyze how the adoption of proportional representation affects fiscal policy. In line with economic theory, we show that proportional systems shift spending toward broad goods (like education and welfare benefits) but decrease spending on geographically targetable goods (like roads). We find little evidence that proportional representation increases the overall size of government. An analysis of the underlying theoretical mechanisms reveals that proportional representation increases electoral turnout, left‐wing representation, and political fragmentation. These changes in political representation explain a substantial share of the rise in education spending, but a small share of the rise in welfare spending or the decline in road expenditures.  相似文献   
42.
This paper examines micro‐level channels through which financial development can affect such macroeconomic outcomes as level of income. Specifically, we investigate theoretically and empirically how financial constraints affect a firm's innovation activities. Theoretical predictions are tested using unique firm survey data, which provide direct measures for innovations and firm‐specific financial constraints, as well as information on shocks to firms' internal funds that serve as firm‐level instruments for financial constraints. We find unambiguous evidence that financial constraints restrain the ability of domestically owned firms to innovate and hence to catch up to the technological frontier.  相似文献   
43.
Romano Piras 《LABOUR》2013,27(2):140-163
We extend the Dolado et al. (1994) model to both inflows and outflows of migrants and assume that they have a human capital endowment that contributes to increase/decrease the stock of human capital in the receiving/sending economy. We derive the conditional convergence equation in which the impact of migration flows on the growth rate is disentangled in a pure quantity effect and in a quality or composition effect of immigration and emigration rates that accounts for the relative human capital endowment of migrants with respect to resident population. Next, we test the model with Italian regional data for the 1970–2005 time period. We find that the model provides a good explanation of the Italian experience. The quantity effect is negative for the immigration rate and positive for the emigration rate, whereas the composition effect is positive for immigration and negative for emigration. Finally, we separate the centre‐north from the south and find that the composition effect of emigration is stronger for the latter. We interpret these results as a clear evidence of a brain drain from the Mezzogiorno to the centre‐northern regions.  相似文献   
44.
A dynamic model of a heterogeneous population is studied. Particles belonging to a population are divided, at every time t, into a finite number of classes according to their types and the partition changes over time. The role of the occupancy numbers, namely the cardinality of each class, is highlighted. The relationship between the stochastic process of occupancy numbers and the process of particle types is analyzed. The main goal of this paper is the estimation of the lifetime of each particle at a given time t, when the observed data are the history of the process of the number of dead particles up to t. Furthermore, a discrete time approximation of the filter is given.  相似文献   
45.
The relative performance of a component of a series system in two different environments is considered. The conditional probability of the failure of the system due to the failure of the specified component given that the system failed before time t is regarded as a measure of relative importance of the component to the system. A U-statistic test for checking the equality of the relative importance of the component to the system in two different environments against the alternative that the relative importance is smaller in one of the environments, is proposed. Some simulation results for estimating the power of the test are reported. The proposed test is applied to one real data set and it is seen that a different aspect of the data is brought out by this comparison than that by the comparisons of the absolute importance functions such as the subsurvival functions, considered in earlier studies.  相似文献   
46.
本文主要论述了十一届三中全会党认识和处理历史问题的主、客条件,即十一届三中全会党能正确地认识和处理历史问题,是承继了党的传统,是历史发展的要求,是时代发展的要求,是党的战略发展的要求,是老一辈无产阶级革命家艰辛努力的结果。  相似文献   
47.
引入域上典型群的生成问题所得的成果;对局部环R上典型群生成问题研究,构造度量函数及一平延,为局部环R上典型群向域F上的典型群导入,给出典型群的非双曲型.  相似文献   
48.
文章介绍了第四代移动通信的概念,主要应用的技术以及4G的发展前景.  相似文献   
49.
作为对经济理论和理论核心的综合和深化,G函数引导出了一些新的探索。其中主要有初始模型的选取,试验焦点的确定,以及实验领域的搜索等。出于对经济理论核心的精确化需要,超越对数函数成为初始结构模型的可选择形式,由此导致数据试验的焦点内容集中。若其他条件不变,作为边界条件,固定数量向量会成为实验的基本出发点,在其中所进行的搜索会日益成为实际验证所关注的内容。  相似文献   
50.
Efromovich-Pinsker and Stein blockwise-shrinkage estimates are traditionally studied via upper-bound oracle inequalities, which bound the estimate's risk from above by the oracle's risk plus a remainder term. These bounds allow one to establish sufficient conditions for attaining the oracle's risk. To explore necessary conditions, this article develops a lower-bound oracle inequality, which bounds the estimate's risk from below by the oracle's risk minus a remainder term. In particular, the lower bound implies that thresholds must vanish for attaining the oracle's risk.  相似文献   
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