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21.
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Marianna Pensky 《Annals of the Institute of Statistical Mathematics》2002,54(1):83-99
The traditional empirical Bayes (EB) model is considered with the parameter being a location parameter, in the situation when the Bayes estimator has a finite degree of smoothness and, possibly, jump discontinuities at several points. A nonlinear wavelet EB estimator based on wavelets with bounded supports is constructed, and it is shown that a finite number of jump discontinuities in the Bayes estimator do not affect the rate of convergence of the prior risk of the EB estimator to zero. It is also demonstrated that the estimator adjusts to the degree of smoothness of the Bayes estimator, locally, so that outside the neighborhoods of the points of discontinuities, the posterior risk has a high rate of convergence to zero. Hence, the technique suggested in the paper provides estimators which are significantly superior in several respects to those constructed earlier. 相似文献
23.
The decay process J/ψ→p X X→p P,where p,p and P are the proton,antiproton and pseudoscalar states,respectively,has been studied in terms of the angular distribution and the generalized moment analysis methods.The result shows that we can identify the spin,but cannot determine the parity of the baryon resonance state X produced in the process J/ψ→p X X→p P. 相似文献
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基础房价的相关指标及其走势一直是大众关心的热门话题.本文通过对上海基础房价相关指标的分析,建立了市场房价走势的两个数学模型.模型一:在相关性分析的基础上利用主成分分析消除指标间的共线性,再用回归拟合房价模型并进行预测;模型二:在相关性分析的基础上利用核估计方法预测出房价.继呵对2005年下半年的房价走势进行了预测,得出的结果与实际情况相吻合. 相似文献
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28.
E. Mathieu Y. Foucher P. Dellamonica J. P. Daures 《Methodology and Computing in Applied Probability》2007,9(3):389-397
In AIDS control, physicians have a growing need to use pragmatically useful and interpretable tools in their daily medical
taking care of patients. Semi-Markov process seems to be well adapted to model the evolution of HIV-1 infected patients. In
this study, we introduce and define a non homogeneous semi-Markov (NHSM) model in continuous time. Then the problem of finding
the equations that describe the biological evolution of patient is studied and the interval transition probabilities are computed.
A parametric approach is used and the maximum likelihood estimators of the process are given. A Monte Carlo algorithm is presented
for realizing non homogeneous semi-Markov trajectories. As results, interval transition probabilities are computed for distinct
times and follow-up has an impact on the evolution of patients.
相似文献
29.
Jiang Wei 《Journal of Mathematical Analysis and Applications》2004,297(1):305-316
The eigenvalue and the stability of singular differential systems with delay are considered. Firstly we investigate some properties of the eigenvalue, then give the exact exponential estimation for the fundamental solution, and finally discuss the necessary and sufficient condition of uniform asymptotic stability. 相似文献
30.
Precise measurement of magnetic moment of short-lived β-emitting nuclei12B ( I π=1+, T 1/2=20.18 ms)
Zhou Dongmei Zheng Yongnan Du Enpeng Xu Yongjun Zhu Jiazheng Yuan Daqing Wang Zhiqiang Luo Hailong Zuo Yi Ma Ruigang Duan Xiao M. Mihara M. Fukuda K. Matsuta T. Minamisono Zhu Shengyun 《中国科学G辑(英文版)》2004,47(5):531-539
The spin polarized β-emitting nuclei12B (I
π=1+,T
1/2=20.18 ms) were produced by the nuclear reaction11B(d, p)12B and by the selection technique of the incident deuteron energy and the12B recoil angle following the nuclear reaction. The nuclear magnetic moment of the short-lived nuclei12B was measured by β-NMR with the β-NMR and β-NQR setup established for the first time in China. The nuclear magnetic moment
of12B was determined to be μ=0.99993±0.00048 nm org=0.99993±0.00048 after the precise correction of the Knight shift. 相似文献