General saddlepoint approximations to distributions under an elliptical population

General saddlepoint approximations are derived for the distributions of statistics under an elliptical population. The technique is applied to obtain the tail probabilities of latent roots of a sample covariance matrix. It is shown that the method based on normalizing transformations by Tsuchiya and Konishi (1997) is efficient for the sample correlation coefficient in an elliptical sample.     

Maximum likelihood estimation for a nearly random walk model

This paper proposes an effective reparameterization method for the maximum likelihood estimation of a nearly random walk ARIMA (1,1,1) model, an important case where standard method of locating the MLE is not satisfactory. This model is equivalent to the permanent and temporary components model that Fama &French (1988) and others used to capture the slow mean reversion behavior of stock prices. The reparameterization method we prppose for estimating the nearly cancelled AR and MA parameters performs satisfactorily. The exact likelihood function based on the transformed parameters is studied. We argue that the region of interest will get magnified and emphasized in the transformed space, thus making the search for MLE more thorough and effective. Substantiai simuiation evidences are provided to demonstrate the effectiveness of the method. The sample size requirement is critical and is discussed in details. For application, this method is applied to estimate a nearly random walk ARIMA (1,1,1) model for NYSE/AMEX value-weighted market return in daily and longer holding-period horizons.     

A Critical Assessment of Simulated Critical Values

There is a wide variety of statistical problems (e.g., unit root and cointegration tests) where hypothesis testing involves the use of simulated rather than theoretical critical values. We argue that, in practice, the number of replications used to simulate critical values is often insufficient to provide the degree of precision that is implied. In particular, the number of replications needed is greatest for values in the tails of the distribution. We provide recommendations for approximating the number of replications needed to achieve a desired degree of precision.     

Power of largest root on canonical correlation

We consider the testing hypothesis that two random vectors of p and q components are independent in canonical correlation analysis. In this paper we investigate the powers of the test based on the largest root criterion. As the exact distribution are expressed by the zonal polynomials, the computation is possible only for p=2, and also it is necessary to calculate using quadruplex precision because we lose the significance by subtraction. So in Table I we obtain the percentage points of the largest root criterion for the computation of the quadruplex precision. Then we calculate the power when p=2 and q = 3 to 11 (2). The results show that for the fixed n–q the power becomes smaller when q increases, and for the fixed p1 of the alternative hypothesis (p1, P2) the power does not become significantly large when P2 increases. We can also find the sample size required for the power agnist some alternative hypothesis to be about 0.9. the numerical results may be useful to find the quality of approximation by using formula of the asyptotic distribution.     

Double samble tests— a distribution free procedure

A method for constructing two-stage (double samble) tests is presented which does not require the evaluation of complicated bivariate distribution function. The procedure results from a modification of Fisher's method for combining independent tests of significance and is distribution free in the way it combines the test results from the two sampies. However, the one sample test statistics for the two samples are assumed to have continuous distributions and may be parametric. A rule is also given or the selection of a particular test out of a family of possible two-stage tests which can be generated by this method. Specific examples are given and comparisons are made with two double sample tests which have previously been presented in the literature.     

略论大众文化

中国 1 3亿人口的大国 ,图书事业飞速发展 ,出版物层出不穷 ,必须去其糟粕 ,取其精华 ,面向大众 ,扎根民众 ,为大众所想 ,为大众所写。坚决反对东搬西抄 (这里东指东方 ,西指西方 ) ,反对洋八股与土八股 ,提倡为大众所接受的文化 ,努力开创中华大众文化的新局面     

毛泽东在商品经济问题上步入误区的思想渊源探析

社会主义时期,毛泽东对商品经济时而肯定,时而否定,并最终走向否定,步入误区.造成这种状况的原因是极其复杂的,但从根本上讲,与毛泽东所接受的马恩关于社会主义社会的设想及中国传统文化中平均主义和大同思想的影响有密切关系.深入探究这一问题,将有助于我们加深对邓小平社会主义市场经济理论的认识和理解.     

Higher-order approximations for interval estimation in binomial settings

In this paper we revisit the classical problem of interval estimation for one-binomial parameter and for the log odds ratio of two binomial parameters. We examine the confidence intervals provided by two versions of the modified log likelihood root: the usual Barndorff-Nielsen's r^*$r^{*}$ and a Bayesian version of the r^*$r^{*}$ test statistic.     

STAR模型中退势单位根检验的小样本性质研究

 Kapetanios et al. (2003)和刘雪燕(2008)提出了ESTAR和LSTAR模型单位根检验的方法。本文将时间序列退势的OLS和GLS方法与他们提出的单位根检验方法结合,通过蒙特卡洛试验发现,在STAR模型中,对时间序列退势能不同程度的改善单位根检验的功效。若时间序列只存在非零均值,ESTAR模型中OLS退势存在优势;LSTAR模型,样本容量较小时（T<=50）,OLS退势的优势较明显,样本容量较大（T>100）时,GLS退势具有了微弱的优势。若序列存在非零的均值和趋势,且样本容量较小时,LSTAR模型中GLS退势的优势较明显,ESTAR模型中OLS退势的优势较明显;样本容量较大时,LSTAR模型中二者功效都很高,ESTAR模型中GLS退势的优势较明显。     

以人为本蕴涵的动力机制与平衡机制

以人为本的动力机制就个体的人性层面来说,包括动因的开发,即不断满足人的合理需要;就社会层面来说,包括动能的开发,即社会应为人的创造个性和创造能力的发挥提供机会和舞台。平衡机制是社会达到和谐、有序状态的重要机制。通过平衡与整合,达到社会的和谐与有序,要靠公正理念的贯彻和执行。以人为本的动力机制与平衡机制两者在理论逻辑上是统一的,在现实当中,两者有时是分裂的,表现为机会、分配和结果三大公正的缺失。其根本原因是权力至上的社会层级结构和“官本位”的政府权力运作体制。