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121.
A nonstationary simultaneous autoregressive model \({X^{(n)}_k=\alpha \Big(X^{(n)}_{k-1}+X^{(n)}_{k+1}\Big)+\varepsilon_k, k=1, 2, \ldots , n-1}\), is investigated, where \({X^{(n)}_0}\) and \({X^{(n)}_n}\) are given random variables. It is shown that in the unstable case α = 1/2 the least squares estimator of the autoregressive parameter converges to a functional of a standard Wiener process with a rate of convergence n 2, while in the stable situation |α| < 1/2 the estimator is biased but asymptotically normal with a rate n 1/2.  相似文献   
122.
本文以陕西省12家纺织企业2009年的观测值为样本,对企业的可持续增长及其获得的财政补贴的相关性进行研究。结果表明:陕西省纺织企业的可持续增长率与财政补贴金额呈显著正相关。另外,企业规模、企业成立年限与财政补贴金额正相关,营业收入增长率与财政补贴金额负相关。  相似文献   
123.
A play-the-winner-type urn design with reduced variability   总被引:1,自引:0,他引:1  
We propose a new adaptive allocation rule, the drop-the-loser, that randomizes subjects in the course of a trial comparing treatments with dichotomous outcomes. The rule tends to assign more patients to better treatments with the same limiting proportion as the randomized play-the-winner rule. The new design has significantly less variable allocation proportion than the randomized play-the-winner rule. Decrease in variability translates into a gain in statistical power. For some values of success probabilities the drop-the-loser rule has a double advantage over conventional equal allocation in that it has better power and assigns more subjects to the better treatment. Acknowledgments. I thank Stephen Durham, the associate editor, and the referees for their helpful suggestions.  相似文献   
124.
125.
The marginal social value of income redistribution is understood to depend on both the concavity of individuals’ utility functions and the concavity of the social welfare function. In the pertinent literatures, notably on optimal income taxation and on normative inequality measurement, it seems to be accepted that the role of these two sources of concavity is symmetric with regard to the social concern about inequality in the distribution of income. Direct examination of the question, however, reveals that this is not the case. Concavity of utility has a simple, direct effect on the marginal social value of redistribution, as might be expected, whereas concavity of the social welfare function has a more subtle influence, one that in some cases may not be very significant. The implications of this difference are examined for some standard forms of utility and welfare functions, including particular versions that appear in the optimal income taxation literature.  相似文献   
126.
目的探讨急腹症手术患者麻醉的护理措施。方法在我院收治的行急腹症手术患者中选取36例,对其麻醉过程所采用的护理措施进行回顾性分析。结果 36例患者中,非常满意25例,比较满意10例,不满意1例,护理总满意度为97.2%。结论在急腹症手术过程中,给予患者良好的护理措施,可有效促进患者病情的恢复,提高患者的护理满意度。  相似文献   
127.
In an economy with private information, we introduce the notion of objects of choice as lists of bundles out of which the market selects one for delivery. This leads to an extension of the model of Arrow–Debreu that is used to study trade ex ante with private state verification. Under the assumption that agents are prudent, equilibrium is characterized by the fact that agents consume bundles with the same utility in states that they do not distinguish. This is a weaker condition than the restriction of equal consumption imposed by Radner (Econometrica 36(1), 31–58, 1968), therefore, some no trade situations are avoided and the efficiency of trade increases.  相似文献   
128.
This paper proposes a theory of institutionally imposed monogamy. In a society where many women are allocated to the elite, there are high returns for the non-elite men to rebel. Monogamy, or “constrained” polygyny, can pacify non-elite men, and thus serve the elite’s reproductive interests. The more unequal is the society, the stricter constraints the elite want to impose on themselves. This suggests how monogamy might have arisen in response to rising class cleavages, e.g., in the wake of the introduction of agriculture. Another result is that, if the elite can write a law that commits not only themselves but also any group that would come to replace them in a rebellion, then polygyny will be more constrained than if they cannot. We speculate that the Church in Europe may have facilitated the imposition of such binding constraints.  相似文献   
129.
Lp空间上线性回归方程回归系数的估计   总被引:1,自引:1,他引:1  
本文讨论了多元线性回归方程参数的L^p估计问题。首先采取消除方程中参数“。的技术,化参数估计为对回归系数的估计,然后进一步将问题转化为一个单目标数学规划模型,利用能自动搜索最优解的电脑软件,十分方便地求出规划模型的最优解。特别对一元回归方程,在消除参数a0后,还可以直接利用普通一元函数求极值的方法,求出回归系数的估计。  相似文献   
130.
This paper contributes to the understanding of the long-run consequences of Roman rule on economic development. In ancient times, the area of contemporary Germany was divided into a Roman and a non-Roman part. The study uses this division to test whether the formerly Roman part of Germany are more developed than the non-Roman part. This is done using the Limes Germanicus wall as geographical discontinuity in a regression discontinuity design framework. The results indicate that economic development—as measured by luminosity—is indeed significantly and robustly larger in the formerly Roman part of Germany. The study identifies the persistence of the Roman road network until the present as an important factor causing this developmental advantage of the formerly Roman part of Germany both by fostering city growth and by allowing for a denser road network.  相似文献   
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