20世纪清代学术史研究回顾

20世纪清代学术史的研究历程可分为三个阶段。前半期 ,梁启超、钱穆等资产阶级史学家在研究中 ,力戒门户之见 ,注重揭示各种学术思潮与流派兴衰的内在因果关系 ,重视汇通中西文化的学术思想及方法论的探讨 ;中后期 ,以侯外庐等为代表的马克思主义史学家用历史唯物主义的理论和方法 ,清理发掘了清代学术史中丰富的思想文化遗产 ;近二十年来 ,清代学术史研究取得了辉煌的成就 ,开拓了许多新的研究领域 ,内容涉及对清代学术史的专题研究 ,也有对清代某个学者的个案研究     

类后现代叙事与20世纪90年代女性“个人化写作”

20世纪90年代女性“个人化写作”是中国当代小说中较为独特的文本之一,按照叙事学的理论,其主要表征是使用后现代的叙事策略与方法。然而,由于这种后现代手法是通过借鉴与模仿而完成的,因此,其实质应当是一种文本上的“类后现代”叙事,这种“类后现代”叙事具有反权威、拆解二元对立模式的倾向,采取“躯体描写”和“姐妹情谊”的文本策略来展示其叙事观念。在艺术上表现为对元小说的应用、破碎结构的采用和对独特语言的使用。虽然20世纪90年代女性“个人写作”在一定程度上引起了中国女性写作在文本叙述上的变革,但也存有自身的精神困境并因此走向了尽头。对此种现象我们应反思。     

依法遏制婚外恋论略

当前,我国每年约有40万个家庭解体,其主要原因就是婚外恋。本文简要分析了婚外恋的特点、原因及其后果,着重阐述了遏制婚外恋的措施,以保护妇女、儿童的合法权益,净化社会风气。     

二十世纪中国农业教育规模的变迁

20世纪中国的农业教育经历了多次重大的发展变革。文章通过对20世纪100年中国农业学校数量、在校学生规模、招生规模等宏观办学指标的统计与梳理,揭示了整个世纪农业教育规模的变迁状况,进而讨论与分析了农业教育规模的发展与国家政治、社会经济发展、教育发展规律等的关系。     

Semiparametric inference of proportional odds model based on randomly truncated data

This paper studies the estimation in the proportional odds model based on randomly truncated data. The proposed estimators for the regression coefficients include a class of minimum distance estimators defined through weighted empirical odds function. We have investigated the asymptotic properties like the consistency and the limiting distribution of the proposed estimators under mild conditions. The finite sample properties were investigated through simulation study making comparison of some of the estimators in the class. We conclude with an illustration of our proposed method to a well-known AIDS data.     

Semiparametric estimation for count data through weighted distributions

This paper is concerned with semiparametric discrete kernel estimators when the unknown count distribution can be considered to have a general weighted Poisson form. The estimator is constructed by multiplying the Poisson estimate with a nonparametric discrete kernel-type estimate of the Poisson weight function. Comparisons are then carried out with the ordinary discrete kernel probability mass function estimators. The Poisson weight function is thus a local multiplicative correction factor, and is considered as the uniform measure to detect departures from the equidispersed Poisson distribution. In this way, the effects of dispersion and zero-proportion with respect to the standard Poisson distribution are also minimized. This method of estimation is also applied to the weighted binomial form for the count distribution having a finite support. The proposed estimators, in addition to being simple, easy-to-implement and effective, also outperform the competing nonparametric and parametric estimators in finite-sample situations. Two examples illustrate this new semiparametric estimation.     

从统计学史解析“自由度”概念

自由度是统计学中一个十分重要而又长期没有被圆满解释的概念。对此,从统计学史角度,对皮尔逊、费歇尔有关自由度问题争论原始文献细致考察,彻底澄清了自由度概念的内涵及与其相关的统计思想,弥补了Fienberg、Stigler与陈希孺已有解释的缺陷。研究表明：皮尔逊关于卡方检验中无论总体分布已知还是其来自于样本推断统计量都具有同一分布的错误判断,导致卡方检验的准确性出现偏差,这种偏差虽被同时代少数几个统计学家察觉但他们却无法解释其根源。费歇尔提出自由度概念并结合n维几何、假设检验与最大似然方法的论证不仅修正了皮尔逊的错误,也完善了从样本统计量估计总体参数的数理逻辑。     

Multivariate inverse Gaussian distribution as a limit of multivariate waiting time distributions

Multivariate inverse Gaussian distribution proposed by Minami [2003. A multivariate extension of inverse Gaussian distribution derived from inverse relationship. Commun. Statist. Theory Methods 32(12), 2285–2304] was derived through multivariate inverse relationship with multivariate Gaussian distributions and characterized as the distribution of the location at a certain stopping time of a multivariate Brownian motion. In this paper, we show that the multivariate inverse Gaussian distribution is also a limiting distribution of multivariate Lagrange distributions, which is a family of waiting time distributions, under certain conditions.     

Optimal consumption and portfolio selection with negative wealth constraints,subsistence consumption constraints,and CARA utility

We consider the optimal consumption and portfolio selection problem with constant absolute risk aversion (CARA) utility. The economic agent in this model receives constant labor income, and her economic behavior is restricted on consumption and wealth, which are called the subsistence consumption constraint and the negative wealth constraint. We use the convex duality method to derive the value function and the optimal policies in closed-form solutions. Also we illustrate some numerical examples.     

A critical look at Lo's modified R/S statistic

We report on an empirical investigation of the modified rescaled adjusted range or R/S statistic that was proposed by Lo, 1991. Econometrica 59, 1279–1313, as a test for long-range dependence with good robustness properties under ‘extra’ short-range dependence. In contrast to the classical R/S statistic that uses the standard deviation S to normalize the rescaled range R, Lo's modified R/S-statistic V_q is normalized by a modified standard deviation S_q which takes into account the covariances of the first q lags, so as to discount the influence of the short-range dependence structure that might be present in the data. Depending on the value of the resulting test-statistic V_q, the null hypothesis of no long-range dependence is either rejected or accepted. By performing Monte-Carlo simulations with ‘truly’ long-range- and short-range dependent time series, we study the behavior of V_q, as a function of q, and uncover a number of serious drawbacks to using Lo's method in practice. For example, we show that as the truncation lag q increases, the test statistic V_q has a strong bias toward accepting the null hypothesis (i.e., no long-range dependence), even in ideal situations of ‘purely’ long-range dependent data.