Real nonparametric regression using complex wavelets

Summary.  Wavelet shrinkage is an effective nonparametric regression technique, especially when the underlying curve has irregular features such as spikes or discontinuities. The basic idea is simple: take the discrete wavelet transform of data consisting of a signal corrupted by noise; shrink or remove the wavelet coefficients to remove the noise; then invert the discrete wavelet transform to form an estimate of the true underlying curve. Various researchers have proposed increasingly sophisticated methods of doing this by using real-valued wavelets. Complex-valued wavelets exist but are rarely used. We propose two new complex-valued wavelet shrinkage techniques: one based on multiwavelet style shrinkage and the other using Bayesian methods. Extensive simulations show that our methods almost always give significantly more accurate estimates than methods based on real-valued wavelets. Further, our multiwavelet style shrinkage method is both simpler and dramatically faster than its competitors. To understand the excellent performance of this method we present a new risk bound on its hard thresholded coefficients.     

主动适应教师教育需要努力提高办学水平——对吉林师范大学发展定位与学科建设若干问题的个案思考

本文从分析吉林师范大学的发展定位与学科建设等具体问题入手,对有关教师教育和普通高师院校发展趋势、前景等一系列重要理论与实践问题进行了探讨.尽快提高办学水平是适应教师教育的迫切需要,准确定位是确定学校发展战略的前提,学科建设是提高办学水平的中心环节,调整优化学科专业结构是学科建设的主要途径.     

反Fuzzy子群的直积

1990年R.Biswas在[2]中提出了反Fuzzy子群的概念.在此基础上本文相应定义了反Fuzzy子群的直积.接着讨论了其包括正规、共轭情况下的若干性质.此外,还给出了直积μ_1×μ_2是G×G上的反Fuzzy子群的一个充要条件.     

Missing data and forecasting in multivariate time series: An application of the common components dynamic linear model

Summary The paper deals with missing data and forecasting problems in multivariate time series making use of the Common Components Dynamic Linear Model (DLMCC), presented in Quintana (1985), and West and Harrison (1989). Some results are presented and discussed: exploiting the correlation between series, estimated by the DLMCC, the paper shows as it is possible to update state vector posterior distributions for the unobserved series. This is realized on the base of the updating of the observed series state vectors, for which the usual Kalman filter equations can be applied. An application concerning some Italian private consumption series provides an example of the model capabilities.     

正烯烃沸点与其分子结构之间定量关系的研究

本文根据分子结构的特点，借助图论探讨了正烯烃的沸点与分子结构的关系，提出了一个具有一定结构基础的定量关系。对４０种正烯烃的计算结果表明，沸点计算值都接近实验值，平均误差仅０．０５４％。     

论高等师范教育实践课程的变革

高师现行沿用的教育实践课程制度存在课时总量不足 ,学科课程与实践课程比例失衡 ;以教育实习为主 ,形式单一、实践与理论隔离、内涵缺失等问题。由此出发 ,教育实践课程改革应在以下层面进行 :增加教育实践课程课时总量 ,使学科课程与实践课程取得动态平衡 ;形成多阶段、多形式的教育实践内容体系 ;整合理论与实践 ,创生新的教育实践模式 ;更新评价理念 ,合理运用多种评价方式。同时 ,教育实践课程改革还要特别关注硬件和软件建设。     

NEAR-ALGEBRA和BANACH代数上的一个特征值定理(英文)

在near-algebra或Banach代数中引入(p,q)-可加自映象f和正则可逆元的概念,得到一个值得注意的结果,即在一定条件下,对于定义在near-algebra或Banach代数X中(p,q)-可加自映象f,X中的任意正则可逆元都具有公共的特征值λ=2q/(1 q),p=q≠?1。     

浅谈师范院校儿童文学的教学工作

儿童文学对儿童的发展至关重要。目前,我国儿童文学教学存在一些问题,要改变这种现状,必须改变人们对儿童文学的偏见。儿童文学要为基础教育服务,必须加强师范院校的儿童文学教学工作,使师范生认识到学习儿童文学的重要性。     

In Memoriam: Emeritus Professor Henry Oliver Lancaster, AO FAA 1 February 1913 – 2 December 2001

The death, in Sydney, of Oliver Lancaster marks the end of an era in the histories of the Statistical Society of Australia, which (in its previous existence as the Statistical Society of New South Wales) he helped found in 1947, and of the Australian Journal of Statistics of which he was founding editor (1959–1971). Oliver Lancaster was Foundation Professor of Mathematical Statistics at the University of Sydney (1959–1978), where he spent his life as student and academic. During his academic career, he achieved scholarly distinction in at least four fields: mathematical statistics, medical and public health statistics, the history of medicine and of statistics, and statistical bibliography. With E.J.G. Pitman (1897–1993), M.H. Belz (1897–1975), E.A. Cornish (1909–1973) and P.A.P. Moran (1917–1988) he was part of a cohort of renowned Australian mathematical statisticians who laid the foundation of the glory days of Australian mathematical statistics. This obituary and tribute focuses on some of these aspects, within a broader historical picture.     

多元正态分布广义方差区间估计的改进

讨论了多元正态分布广义方差的区间估计问题,给出了在覆盖率及长度上均优于最优仿射同变区间估计的改进估计．