加强网络道德建设

随着计算机网络的发展,在21世纪将形成一个与当代工业社会具有不同特征的现代网络社会.现代网络社会作为一个"虚拟"的社会,也是一个充满问题与矛盾的真实社会.它同当代工业社会一样,需要道德建设的支撑.网络道德建设是一项复杂的系统工程.加强网络道德建设具有十分重要的现实意义.     

Regression Analysis of Left-truncated and Case I Interval-censored Data with the Additive Hazards Model

In recent years the analysis of interval-censored failure time data has attracted a great deal of attention and such data arise in many fields including demographical studies, economic and financial studies, epidemiological studies, social sciences, and tumorigenicity experiments. This is especially the case in medical studies such as clinical trials. In this article, we discuss regression analysis of one type of such data, Case I interval-censored data, in the presence of left-truncation. For the problem, the additive hazards model is employed and the maximum likelihood method is applied for estimations of unknown parameters. In particular, we adopt the sieve estimation approach that approximates the baseline cumulative hazard function by linear functions. The resulting estimates of regression parameters are shown to be consistent and efficient and have an asymptotic normal distribution. An illustrative example is provided.     

Model Averaging for Prediction With Fragmentary Data

ABSTRACT

One main challenge for statistical prediction with data from multiple sources is that not all the associated covariate data are available for many sampled subjects. Consequently, we need new statistical methodology to handle this type of “fragmentary data” that has become more and more popular in recent years. In this article, we propose a novel method based on the frequentist model averaging that fits some candidate models using all available covariate data. The weights in model averaging are selected by delete-one cross-validation based on the data from complete cases. The optimality of the selected weights is rigorously proved under some conditions. The finite sample performance of the proposed method is confirmed by simulation studies. An example for personal income prediction based on real data from a leading e-community of wealth management in China is also presented for illustration.     

文姜小议

春秋时齐国女子文姜因性生活问题，遭到后人多方面的贬斥.文姜出嫁鲁国后，鲁国在齐鲁争强中逐渐失势，文姜数度以国君之礼与齐国国君会晤，协调齐鲁关系，增强了鲁国的实力和地位，但史家们却未给予应有的评价.本文认为，文姜不失为古代一位颇有才能的女外交家，不应以瑕掩瑜.     

对学校法制教育状况的反思

本文对学校法制教育的理念、教育实效和课程构建等问题加以探究。     

流动蒸汽在正弦型纵槽管内凝结换热的实验研究

本文从实验的角度出发,对正弦型剖面的纵槽管进行了研究。找出了局部换热量与纵向坐标的关系。在拟合准则方程时,文中引进了一个新的特征参数L_c。并以此得到无量纲纵坐标z/L_c替代其他学者用实验段管长L来得到无量纲纵坐标z/L。且指出了原方法的不足之处。     

Establishing decision tree-based short-term default credit risk assessment models

ABSTRACT

Traditional credit risk assessment models do not consider the time factor; they only think of whether a customer will default, but not the when to default. The result cannot provide a manager to make the profit-maximum decision. Actually, even if a customer defaults, the financial institution still can gain profit in some conditions. Nowadays, most research applied the Cox proportional hazards model into their credit scoring models, predicting the time when a customer is most likely to default, to solve the credit risk assessment problem. However, in order to fully utilize the fully dynamic capability of the Cox proportional hazards model, time-varying macroeconomic variables are required which involve more advanced data collection. Since short-term default cases are the ones that bring a great loss for a financial institution, instead of predicting when a loan will default, a loan manager is more interested in identifying those applications which may default within a short period of time when approving loan applications. This paper proposes a decision tree-based short-term default credit risk assessment model to assess the credit risk. The goal is to use the decision tree to filter the short-term default to produce a highly accurate model that could distinguish default lending. This paper integrates bootstrap aggregating (Bagging) with a synthetic minority over-sampling technique (SMOTE) into the credit risk model to improve the decision tree stability and its performance on unbalanced data. Finally, a real case of small and medium enterprise loan data that has been drawn from a local financial institution located in Taiwan is presented to further illustrate the proposed approach. After comparing the result that was obtained from the proposed approach with the logistic regression and Cox proportional hazards models, it was found that the classifying recall rate and precision rate of the proposed model was obviously superior to the logistic regression and Cox proportional hazards models.     

On the relative accuracy of certain bootstrap procedures

We show the second-order relative accuracy, on bounded sets, of the Studentized bootstrap, exponentially tilted bootstrap and nonparametric likelihood tilted bootstrap, for means and smooth functions of means. We also consider the relative errors for larger deviations. Our method exploits certain connections between Edgeworth and saddlepoint approximations to simplify the computations.     

职业生涯研究

一职业构成状况是社会学研究中重要的变量之一。从宏观的角度看,一个社会的职业构成表明了该社会的分工水平;从微观角度看,社会行动者从事的某种职业说明着个人的社会地位。这两方面多在传统社会学研究中有所体现,其研究更多地具有结构性特征。职业生涯概念的引入力图对此有所突破,一方面它试图把宏观层面和微观层面的职业研究相结合,既关注社会行动者在劳动分工中占有的一系列职业地位,也关注社会行动者职业变动背后的社会因素;另一方面,它也试图把过程因素与结构因素相结合,个人的职业发展或职业连续性的变动在职业生涯的概念下成为社会的…     

白先勇小说同性恋者的悲剧命运探微

白先勇的小说脍炙人口,其中不乏以同性恋为题材的小说。1988年,白先勇公开了自己的性取向。因此,从白先勇的小说看同性恋的世界,不再是雾里看花。白先勇以他独特的小说技巧描述同性恋者的悲剧命运。同性恋者的命运是充满悲剧的,同性恋者一生被流在血液里的生理欲望孽魔纠缠。年轻俊美时,尚能容易满足生理欲望孽魔的需要;随着时光流逝,年岁增长,面容逐渐衰老,再也无法轻易满足生理欲望孽魔的需要。为此,老同性恋者得奔波劳碌、伺机寻找可以满足他们生理欲望孽魔需要的青春鸟,不少的同性恋者也因着得了爱滋病而离开世界。同性恋者一生的命运是悲哀的,白先勇悲天悯人的情怀让读者更深入地了解了同性恋者的世界和他们黑暗的国度。