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91.
Huang Caixie 《佛山科学技术学院学报(社会科学版)》1992,(6)
论述了德布罗意公式不属于量子力学理论体系中的公式。指出梁绍荣等编的《量子力学》一书中,用德布罗意公式推导出自由粒子的波函数的错误。本文用量子力学理论推导出自由粒子的波函数。 相似文献
92.
Lakhbir Singh Hayre 《Journal of statistical planning and inference》1982,6(2):127-130
It is shown that a two population sequential probability ratio test studied by a number of recent authors in the context of sequential medical trials is asymptotically optimal. 相似文献
93.
Bounded-width sequential confidence intervals and sequential tests for regression parameter based on M-estimators are extended to the case where the score-functions generating the M-estimators have jump-discontinuities. In the context of the asymptotic normality of the stopping variable, for the confidence interval problem, it is observed that the jump-discontinuities induce a slower rate of convergence. The proofs of the main theorems rest on the weak convergence of some related processes and this is also studied. 相似文献
94.
The paper uses a meta-analysis to comparatively evaluate the literature addressing the aggregate relationship between a populations age structure and fertility, as hypothesized by Richard Easterlin. The analysis is based on 334 estimated effects retrieved from 19 studies. The results suggest that several factors undermine the empirical support of the Easterlinian age structure/fertility link. These include the neglect of income, the use of relative cohort size to characterize the age structure, mis-specifications of the relevant age-cohorts, as well as the functional form and estimation technique. The results also suggest that the sample of published estimates possibly suffers from two types of publication bias, an under-representation of insignificant effects for small samples, and bias towards supportive effects in the earlier years followed by a bias towards negative effects as the literature matured.All correspondence to: Brigitte Waldorf. The authors appreciate the insightful comments and suggestions from two anonymous reviewers. The research also benefited from discussions with participants of the International Colloquium on Meta-analysis in Economics, Free University, Amsterdam, The Netherlands, December 2002. Finally, we would like to thank David Brown, Meagan Cahill, Angela Donelson, Calvin Farris, and Melaney Seacat from the University of Arizona for their research assistance. Responsible editor: Junsen Zhang. 相似文献
95.
Dan Anbar 《Journal of statistical planning and inference》1978,2(2):153-163
A stochastic approximation procedure of the Robbins-Monro type is considered. The original idea behind the Newton-Raphson method is used as follows. Given n approximations X1,…, Xn with observations Y1,…, Yn, a least squares line is fitted to the points (Xm, Ym),…, (Xn, Yn) where m<n may depend on n. The (n+1)st approximation is taken to be the intersection of the least squares line with y=0. A variation of the resulting process is studied. It is shown that this process yields a strongly consistent sequence of estimates which is asymptotically normal with minimal asymptotic variance. 相似文献
96.
This paper studies the effects of managerial delegation in a duopoly game under alternative unionization structures. Introducing managerial delegation in a framework with centralized unionization leads to incentives for sales, lower profits and higher consumer surplus as well as overall welfare. In contrast, delegating output decisions to managers in the presence of decentralized unionization produces opposite results unless unions are strongly employment‐oriented. Moreover, managerial delegation makes unionization structure neutral in relation to consumer surplus and overall efficiency. Finally, the timing of moves in the three‐stage game proves to be important for obtaining the above qualitative results under decentralized unionization. 相似文献
97.
We study the endogenous formation of R&D networks between two domestic and one foreign firms in a unionized oligopoly. We find that the equilibrium networks are sensitive to the extent of knowledge spillovers between networked firms. If spillovers are sufficiently low, the complete network will arise in equilibrium; however, if spillovers are sufficiently high, the foreign partial network that includes a domestic and a foreign firm will arise. Moreover, for intermediate spillovers, no equilibrium network emerges. These results have implications for aggregate outcomes: equilibrium networks are not necessarily optimal in terms of aggregate effective R&D and aggregate firm profits. 相似文献
98.
王俊霞 《齐齐哈尔大学学报(哲学社会科学版)》2014,(5):180-182
对二语习得的研究表明,母语迁移是影响第二语言习得的重要因素之一。本文通过对英汉两种语言的对比分析,从语音,词汇,语法,文化等诸多方面阐明母语迁移中的负迁移现象对二语习得的影响,并探究了在英语教学过程中如何尽量避免母语负迁移,以使二语习得者的语言能力得到有效提升。 相似文献
99.
Data in many experiments arises as curves and therefore it is natural to use a curve as a basic unit in the analysis, which is in terms of functional data analysis (FDA). Functional curves are encountered when units are observed over time. Although the whole function curve itself is not observed, a sufficiently large number of evaluations, as is common with modern recording equipment, is assumed to be available. In this article, we consider the statistical inference for the mean functions in the two samples problem drawn from functional data sets, in which we assume that functional curves are observed, that is, we consider the test if these two groups of curves have the same mean functional curve when the two groups of curves without noise are observed. The L 2-norm based and bootstrap-based test statistics are proposed. It is shown that the proposed methodology is flexible. Simulation study and real-data examples are used to illustrate our techniques. 相似文献
100.
Zuo (2004) investigated the simplified replacement finite sample breakdown point of weighted L p -depth and L p -median for some appropriate weight functions. The addition breakdown point of weighted L p -depth functions is studied firstly in this article. In addition, for some other weight functions different from those in Zuo (2004), we establish the lower bounds of these two types of breakdown point of weighted L 2-median. 相似文献