Skew-normal alpha-power model

In this paper, authors study properties and inference for the newly introduced skew-normal alpha-power model, generalizing both, the power-normal and skew-normal models. Inference is approached via maximum likelihood. Fisher information matrix is derived and shown to be nonsingular at the whole parametric space. Special emphasis is placed on the special case of the power–skew-normal model. Studies with real data illustrate the fact that the model can be very useful in applications, being able to overfit less general models entertained in the literature.     

Evaluation of the parameters of su by rational fractions

A rational fraction approximation is given for a function of one of the parameters defining Johnson's S_UError assessment for a segment of the domain of validity shows remarkable accuracy.     

Estimation of gaussian mixtures with rotationally invariant covariance matrices

Homoscedastic and heteroscedastic Gaussian mixtures differ in the constraints placed on the covariance matrices of the mixture components. A new mixture, called herein a strophoscedastic mixture, is defined by a new constraint, This constraint requires the matrices to be identical under orthogonal trans¬formations, where different transformations are allowed for different matrices. It is shown that the M-step of the EM method for estimating the parameters of strophoscedastic mixtures from sample data is explicitly solvable using singular value decompositions. Consequently, the EM-based maximum likelihood estimation algorithm is as easily implemented for strophoscedastic mixtures as it is for homoscedastic and heteroscedastic mixtures. An example of a “noisy” Archimedian spiral is presented.     

“90后”大学生入学适应的困境与化解路径选择

"90后"走进大学校园后,存在着适应大学生活的困难,应依据他们所具有的时代特点进行消解路径的选择,在高校开展新生入学教育时应注重更新教育内容、创新教育形式、调整教育时间、整合教育资源,帮助这一代大学新生尽快适应大学生活。     

R–estimation of normed bivariate density functions

Normed bivariate density funtions were introduced by HOEFFDING (1940/41). In the present paper estimators for normed bivariate ranks and on a FOURIER series expansion in LEGENDRE polynomials. The estimation of normed bivarate density functions under positive dependence is also described     

Studying the dependence between ordinal-nominal categorical variables via orthogonal polynomials

In situations where the structure of one of the variables of a contingency table is ordered recent theory involving the augmentation of singular vectors and orthogonal polynomials has shown to be applicable for performing symmetric and non-symmetric correspondence analysis. Such an approach has the advantage of allowing the user to identify the source of variation between the categories in terms of components that reflect linear, quadratic and higher-order trends. The purpose of this paper is to focus on the study of two asymmetrically related variables cross-classified to form a two-way contingency table where only one of the variables has an ordinal structure.     

国际冲突：概念、类型与解决

国际冲突是国际行为主体之间经常发生的国际现象，是国际政治学研究的重要内容。本文对国际冲突的概念、类型与解决作了学术上的梳理、审视与辨识，以便为人们正确认识纷繁复杂的国际现象提供理论范式，为学科的进一步发展构筑框架基石。     

Max-min DEA模型及效率讨价还价均衡解

建立一类新的DEA模型,即Max-min DEA模型.该模型通过最大化最小效率单元的效率,结合了自评与互评的思路,在一定程度上克服了仅仅采用自评思想的经典DEA模型的缺陷.文中Max-min均衡模型问题在于保护“弱小”单元的同时,有可能损害其它单元的效率.为克服该问题,文章通过Nash讨价还价模型求解Max-min均衡模型与CCR模型的讨价均衡解.最后用算例进行了演示计算.     

DEA评价模型应用的几点探讨

为更好地应用ＤＥＡ评价模型，本文讨论了ＤＥＡ模型中定性指标的模糊处理及权重分布的随机处理，运用主成分分析法对ＤＥＡ模型指标体系进行处理，并对ＤＥＡ评价结果进行了排队分析．     

二阶非线性时滞微分方程解的渐近性

本文建立了二阶非线性时滞微分方程解的渐近性结果及全局吸引定理,改进和推广了二阶线性方程和一阶非线性方程的已知定理。