Analyzing multiple vector autoregressions through matrix-variate normal distribution with two covariance matrices

Abstract

This article proposes a new approach to analyze multiple vector autoregressive (VAR) models that render us a newly constructed matrix autoregressive (MtAR) model based on a matrix-variate normal distribution with two covariance matrices. The MtAR is a generalization of VAR models where the two covariance matrices allow the extension of MtAR to a structural MtAR analysis. The proposed MtAR can also incorporate different lag orders across VAR systems that provide more flexibility to the model. The estimation results from a simulation study and an empirical study on macroeconomic application show favorable performance of our proposed models and method.     

关于有限群的可解性

利用极大子群的几乎正规的概念得到了有限群为可解群的若干充要条件．     

关于股份台作制股权设置的完善探讨

股份合作制有其制度优势,特别适合小企业,资本与劳动的矛盾不是股份合作制的制度障碍,并对股权设置中的共有产权、资本与劳动关系、经营者积极性、治理结构、转让与筹资等问题提出我们的改进思路与方法。     

我国目前“村民自治”研究的两个问题

进入 2 1世纪 ,村民自治研究的重点发生了转移 ,研究的路径也呈现出多样化的趋势。由村民自治引发的诸问题成为研究的重点 ,其中以村级治理、村民自治中的乡村关系和国家与农民的关系等问题成为了重中之重。但存在的问题也是明显的 ,在研究方法的选择上、在研究理论的偏好上以及在对村民自治制度相关问题的分析上还显不足。可以预计今后村民自治研究的走向是 :关于应用研究和基础理论研究等诸问题将成为关注的焦点 ,在研究的方法选择上将更具多样性和灵活性     

国内报纸应天天发社论之我见

国内报纸天天发社论以同国际报章接轨，也绝不会改变其为党和人民之喉舌的性质。然而，建国50年来至今，本应舆论先行，此项接轨却反倒滞后了。必须正本清源，还社论天天见报的本来面目，期待更多的报纸在《北京青年报》每日社评的形式上能“青出于蓝而胜于蓝”。     

Simple detection of outlying short time series

Sets of relatively short time series arise in many situations. One aspect of their analysis may be the detection of outlying series. We examine the performance of standard normal outlier tests applied to the means, or to simple functions of the means, of AR(1) series, not necessarily of equal lengths. Although unequal lengths of series implies that the means have unequal variances, that are only known approximately, it is shown that nominal significance levels hold good under most circumstances. Thus a standard outlier test can usefully be applied, avoiding the complication of estimating the time series' parameters. The test's power is affected by unequal lengths, being higher when the slippage occurs in one of the longer series     

需要·价值·利益

需要、价值与利益三个范畴,是人类生活中三种既密切相关又有本质区别的重要现象在观念上的反映,也是马克思主义哲学中的三个基础性范畴。需要、价值与利益都是反映主客体关系的范畴,需要侧重的是主体对客体存在着某种要求的矛盾关系,价值侧重的是客体属性与主体需要之间存在的客观上的一致关系,利益侧重的是客体属性对整个主体生存与发展的积极的影响关系。     

中国古代农村土地制度研究刍议

本文介绍了20世纪80年代以后中国古代农村土地制度的研究状况,从实证研究的角度进行了评议,对土地制度如何研究评价提出了新的见解.     

Distributions generated by perturbation of symmetry with emphasis on a multivariate skew t-distribution

Summary . A fairly general procedure is studied to perturb a multivariate density satisfying a weak form of multivariate symmetry, and to generate a whole set of non-symmetric densities. The approach is sufficiently general to encompass some recent proposals in the literature, variously related to the skew normal distribution. The special case of skew elliptical densities is examined in detail, establishing connections with existing similar work. The final part of the paper specializes further to a form of multivariate skew t -density. Likelihood inference for this distribution is examined, and it is illustrated with numerical examples.     

Kurtosis modelling by means of the J-transformation

Summary: The H–family of distributions or H–distributions, introduced by Tukey (1960; 1977), are generated by a single transformation of the standard normal distribution and allow for leptokurtosis represented by the parameter h. Alternatively, Haynes et al. (1997) generated leptokurtic distributions by applying the K–transformation to the normal distribution. In this study we propose a third transformation, the so–called J–transformation, and derive some properties of this transformation. Moreover, so-called elongation generating functions (EGFs) are introduced. By means of EGFs we are able to visualize the strength of tail elongation and to construct new transformations. Finally, we compare the three transformations towards their goodness–of–fit in the context of financial return data.